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Francesca PARENTI

Professore Associato
Dipartimento di Scienze Chimiche e Geologiche - Sede Dipartimento di Scienze Chimiche e Geologiche

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Pubblicazioni

2023 - A Trifunctional ATRP Initiator Bearing Adaptable Bonds [Poster]
Scurani, Giulia; Braidi, Niccolo'; Porcelli, Nicola; Tassinari, Francesco; Parenti, Francesca
abstract

Atom Transfer Radical Polymerization (ATRP) allows for the production of polymers with precise control over molecular weight, dispersity, topology, composition, and functionality. Functional groups can be introduced into the polymer through post-functionalization of chain ends, or on the alkyl residue of the initiator, or by introducing functionalized (co)monomers, greatly greatly enhancing the targetable applications. In addition, the desired functional group can also be carried by the ATRP initiator. Some researchers have explored initiators with hydrolysis- or heat-sensitive functionalities to impart self-healing properties to the final polymer. However, the commonly used aliphatic halide ester initiators have shown poor thermal stability. To address this issue, we recently developed a novel bifunctional benzamide-containing initiator employed in ARGET ATRP of styrene, demonstrating enhanced thermal stability. Covalent Adaptable Networks (CANs) have emerged as a solution for improving the recyclability of thermoset materials. CANs can reorganize connectivity between chains upon thermal treatment, enabling reprocessing. Our goal is to modify the structure of the benzamide-containing initiator to develop a trifunctional initiator bearing adaptable bonds.

2023 - Growth Dynamics of Ultrathin Films of Benzo[1,2-b:4,5-b']dithiophene Derivatives on Au(111): A Photoelectron Spectroscopy Investigation [Articolo su rivista]
Stummo, Angelo; Montecchi, Monica; Parenti, Francesca; Vanossi, Davide; Fontanesi, Claudio; Capelli, Raffaella; Pasquali, Luca
abstract

: Ultrathin films of a stereoisomeric mixture of benzo[1,2-b:4,5-b']dithiophene derivatives were grown by thermal evaporation in vacuum on Au(111), and they were studied in situ by photoelectron spectroscopy. X-ray photons from a non-monochromatic Mg Kα conventional X-ray source and UV photons from a He I discharge lamp equipped with a linear polarizer were used. He I photoemission results were compared with density functional theory (DFT) calculations: density of states (DOS) and 3D molecular orbital density distribution. Au 4f, C 1s, O 1s, and S 2p core-level components suggest a surface rearrangement as a function of film nominal thickness, with the variation of the molecular orientation, from flat-laying at the initial deposition to tilted toward the surface normal at coverages exceeding 2 nm. Eventually, the DFT results were exploited in assigning of the valence band experimental structures. Moreover, polarization-dependent photoemission confirmed the tilted arrangement of the molecules, starting at 2 nm. A variation of the work function of 1.4 eV with respect to the clean substrate was measured, together with a valence band offset of 1.3 eV between the organic layer and gold.

2023 - Influence of chirality on the aggregation of a new A-π-D-π-A small molecule with a benzodithiophene core: Spectroscopic and morphological investigations [Articolo su rivista]
Parenti, Francesca; Capelli, Raffaella; Mucci, Adele; Mortalò, Cecilia; Paolicelli, Guido; Pigani, Laura; Vanossi, Davide; Caselli, Monica
abstract

2023 - Influences of nitrogen base excess on ARGET ATRP of styrene with ascorbic acid acetonide and traces of oxygen and water [Articolo su rivista]
Braidi, N; Parenti, F; Scurani, G; Tassinari, F; Buffagni, M; Bonifaci, L; Cavalca, G; Pettenuzzo, N; Ghelfi, F
abstract

Ascorbic acid is a promising regenerating agent for Activators ReGenerated by Electron Transfer Atom Transfer Radical Polymerization (ARGET ATRP) thanks to its sustainability and environmental friendlyness. The ascorbate anion has even more potential because it has a higher kinetic rate constant of reduction toward the copper catalyst than its protonated counterpart. Although ascorbic acid can be easily neutralized with inorganic bases, the resulting heterogeneous system in the polymerization of hydrophobic monomers (such as styrene) is not well-suited for industrial applications. To overcome this problem, in this study we investigate the use of ascorbic acid acetonide, a more lipophilic derivative, together with soluble nitrogen bases of different basicity. The results show how the pK(a) of the protonated form of the nitrogen base affects the process, especially in the presence of traces of water and/or oxygen. Additionally, we report that milder bases yield better results in terms of dispersity and chain-end fidelity, while high pK(a) bases lead to a complete loss of control.

2022 - Basicity Can Choregraph Regeneration in Homogeneous ARGET ATRP of Styrene [Poster]
Braidi, Niccolo'; Galanti, Marco; Scurani, Giulia; Parenti, Francesca
abstract

There are two drawbacks in the use of H2AA when polymerizing a hydrophobic monomer such as styrene. First, the low solubility of the reducing agent in non-aqueous solvents. Second, the reduction kinetic rate constant of the catalyst by H2AA is around two-orders of magnitude lower than that of ascorbate (HAA–). In non-dissociating solvents this means that the polymerization is much slower since it is strictly related to the amount of reduced catalyst. To overcome this, we employed for the first time a more lipophilic ascorbic acid derivative (5,6-isopropylidene ascorbic acid) in place of H2AA, complemented by nitrogen bases of varying basicity: trimethylpyridine (TMP), diisopropylethylamine (DIPEA), and 1,8-diazabicyclo(5.4.0)undec-7-ene (DBU). The resulting system is an efficient and effective, homogeneous ARGET ATRP of styrene. Furthermore, it highlighted how basicity influences the concentration of radicals, and thus control over the final product.

2022 - EVALUATION OF α,ω UNSATURED POLYSTIRENE VS DIVINYLBENZENE AS CROSSLINKING AGENT IN STYRENE FREE RADICAL POLYMERIZATION [Poster]
Bedogni, Elena; Braidi, Niccolo'; Bonifaci, Luisa; Cavalca, Gianfranco; Ghelfi, Franco; Longo, Aldo; Morandini, Ida; Parenti, Francesca; Pettenuzzo, Nicolò; Piccinini, Sofia
abstract

Telechelic polymers have grown in interest over the past decade thanks also to the evaluation of vitrimers and their properties with high added value (e.g.: recycling efficiency). In this context we propose an evaluation study of replacing a component such as divinylbenzene with a short telechelic alkene-ended polystyrene (α,ω-dienePS). This can be produced by dehydrochlorination of a dihalide-terminated precursor obtained by Atom Transfer Radical Polymerization (ATRP)

2022 - MAY POST-ARGET ATRP FUNCTIONALIZATION BE A GOOD WAY FOR POLYSTYRENE UP-CYCLING? [Poster]
Braidi, Niccolo'; Bedogni, Elena; Bonifaci, Luisa; Cavalca, Gianfranco; Ghelfi, Franco; Longo, Aldo; Morandini, Ida; Parenti, Francesca; Pettenuzzo, Nicolò; Piccinini, Sofia
abstract

The notoriously poor (bio)degradability of vinyl polymers is due to their chemically stable backbone. To lower their environmental impact, it is strategic to intercalate labile bonds along the backbone. These weaker bonds could then be broken faster under environmental conditions, releasing more easily (bio)degradable fragments. By intercalation of disulfide bonds, chemical upcycling is also made possible since the released fragments have the same functionality at both ends (thiol-terminated telechelic shorter chains). These fragments can thus undergo polycondensation, either to reform the starting polymer or to be copolymerized into a novel material. The pursue of sustainability in polymers should show both in the final product as well as in the employed synthetic route. Meaning that, a sensible procedure to intercalate said labile bonds should be employed.

2022 - Novel Bifunctional Amide-Based Initiator for the Atom Transfer Radical Polymerization of Styrene with Ascorbic Acid Acetonide as Reducing Agent [Poster]
Scurani, Giulia; Braidi, Niccolo'; Tassinari, Francesco; Parenti, Francesca
abstract

This study focuses on the synthesis and characterization of a new bifunctional benzamide initiator, CMB2HexDA, for the production of thermostable α,ω-dichloropolystyrene via ARGET ATRP. The motivation behind this research is the need to obtain functionalized polystyrene that can withstand the high temperatures used in industrial extrusion processes, as well as the previous development of a method to obtain α,ω-dialkenepolystyrene by solventless thermal dehydrohalogenation. The commonly used initiators in ATRP undergo thermal fragmentation, leading to chain length reduction and loss of telechelicity. The synthesized initiator was purified and characterized, and the resulting α,ω-dichloropolystyrenes were analyzed through GPC and NMR. The telechelic polystyrene produced with the new initiator exhibited enhanced thermal stability compared to aliphatic-halide ester initiators. Although the specific diamine used does not confer specific functionality, the developed synthetic pathway allows for the introduction of other functionalities into thermostable polystyrenes. Furthermore, the benzamidic function could be exploited to achieve controlled chemical degradation of polystyrene, resulting in more readly degradable oligomeric fragments.

2021 - ARGET ATRP of styrene in EtOAc/EtOH using only Na2CO3 to promote the copper catalyst regeneration [Articolo su rivista]
Braidi, Niccolo'; Buffagni, Mirko; Ghelfi, Franco; Parenti, Francesca; Gennaro, Armando; Isse, Abdirisak A.; Bedogni, Elena; Bonifaci, Luisa; Cavalca, Gianfranco; Ferrando, Angelo; Longo, Aldo; Ida Morandini, And
abstract

“Activator regenerated by electron transfer” “atom transfer radical polymerization” (ARGET ATRP) process catalyzed by CuCl /tris(2-pyridylmethyl)amine (TPMA) (1/1) in ethyl acetate/ethanol (EtOAc/EtOH) for the polymerization of styrene from ethyl 2,2-dichloropropanoate (EDCP) is described. The (re)generation of the activating Cu complex is accomplished by Na CO without the addition of any explicit reducing agent. Differently from the analogous process operating in the presence of ascorbic acid/carbonate as the reducing system, branching is not present and control over polymerization is improved. The activation mechanism should follow a composite route, where both EtOH and TPMA contribute to the regeneration of the catalyst. The oxidation of TPMA is suggested by the absence of the ligand in the final reaction mixture and by the reduction of Cu even in t-BuOAc/t-BuOH, notwithstanding the very poor ability of t-BuOH as a reducing agent. Oxidative degradation of TPMA causes a progressive malfunctioning of the redox catalyst. Consequently, the polymerization rate, after a prompt start, becomes slower and slower, fixing conversions at around 50% (4.5 h). This means a gradual decrease of the free radical concentration, which develops unfavorable conditions for the reductive coupling (termination) between the bifunctional growing chains, preserving a controlled growth of the polymer.

2021 - Copper-catalyzed ARGET ATRP of styrene from ethyl α-haloisobutyrate in EtOAc/EtOH, using ascorbic acid/Na2CO3 as reducing system [Articolo su rivista]
Borsari, M.; Braidi, N.; Buffagni, M.; Ghelfi, F.; Parenti, F.; Porcelli, N.; Serafini, G.; Isse, A. A.; Bonifaci, L.; Cavalca, G.; Longo, A.; Morandini, I.; Pettenuzzo, N.
abstract

Atom transfer radical polymerization (ATRP) is one of the most powerful techniques to synthesize precisely tailored polymers and macrostructures. Activators regenerated by electron transfer (ARGET) ATRP was developed as a “green” strategy to decrease the load of the metal catalyst. However, ARGET ATRP usually uses not-so-green reducing agents (e.g. Sn2+) or expensive and industrially impractical procedures. For these reasons, we report an ARGET ATRP of styrene with various carbonates as reducing agents, both alone and paired with ascorbic acid (AA), using monofunctional initiators and Cl or Br as exchanging atoms. The solvent mixture is composed of the green combination of EtOAc and EtOH, even in the presence of modest amounts of H2O. Cyclic voltammetry was used to evaluate the effect of H2O on the catalyst, as well as the absence of AA. The system returned high yields and low dispersities with low amounts of catalyst (~60 ppm) and moderate reaction times. Excellent results were obtained only with the Cl-ATRP system. NMR spectroscopy and kinetic analyses proved the livingness of the final polymer chains.

2021 - Enhanced gold adhesion on sodium alginate films for green electronics: study of the role of oxygenated functional groups [Poster]
Lorenzi, Francesco; Capelli, Raffaella; Mortalò, Cecilia; Mucci, Adele; Parenti, Francesca
abstract

Sodium alginate (SA) is a natural widespread polysaccharide whose constitutional repeating unit is made of alternating mannuronic and guluronic moieties. Transparent, freestanding and flexible films can be obtained from aqueous solutions of SA, making this green polymer very appealing for several uses [1]. When green electronic components are concerned, a thin gold conducting layer with outstanding adhesion can be deposited on SA flexible substrates by sputtering techniques [2]. In fact, as evidenced by a scotch tape test, the adhesion of the metal layer on SA is much stronger than that observed when the thermal evaporation technique is used for Au deposition. To gain insights on the origin of this strong interaction and to understand if it is more of a chemical or physical nature, here we synthesize a series of hydrophobically modified SAs bearing amide or ester groups in place of the carboxyl and/or the hydroxyl groups of the backbone, which are supposed to form complexes with gold. After thoroughly characterization of the polymers, by IR, 1H and 13C NMR spectroscopies, thermogravimetric and elemental analysis, we obtained modified SAs films which were covered whit a thin gold layer by sputtering techniques. [1] X. Guo et al. Int. J. Biol. Macromol. 162 (2020) 618–628. [2] P. Maccagnani et al. Adv. Sustainable Syst. 1900001 (2019).

2021 - Unusual Cross-Linked Polystyrene by Copper-Catalyzed ARGET ATRP Using a Bifunctional Initiator and No Cross-Linking Agent [Articolo su rivista]
Braidi, Niccolò; Buffagni, Mirko; Buzzoni, Valentina; Ghelfi, Franco; Parenti, Francesca; Focarete, Maria Letizia; Gualandi, Chiara; Bedogni, Elena; Bonifaci, Luisa; Cavalca, Gianfranco; Ferrando, Angelo; Longo, Aldo; Morandini, Ida; Pettenuzzo, Nicolò
abstract

2020 - Copper-Catalysed “Activators Regenerated by Electron Transfer” “Atom Transfer Radical Polymerisation” of Styrene from a Bifunctional Initiator in Ethyl Acetate/Ethanol, Using Ascorbic Acid/Sodium Carbonate as Reducing System [Articolo su rivista]
Braidi, Niccolo'; Buffagni, Mirko; Ghelfi, Franco; Imperato, Manuel; Menabue, Alberto; Parenti, Francesca; Gennaro, Armando; Isse, Abdirisak A.; Bedogni, Elena; Bonifaci, Luisa; Cavalca, Gianfranco; Ferrando, Angelo; Longo, Aldo; Morandini, Ida
abstract

2020 - Quantum dynamics of a single molecule magnet on superconducting Pb(111) [Articolo su rivista]
Serrano, G.; Poggini, L.; Briganti, M.; Sorrentino, A. L.; Cucinotta, G.; Malavolti, L.; Cortigiani, B.; Otero, E.; Sainctavit, P.; Loth, S.; Parenti, F.; Barra, A. -L.; Vindigni, A.; Cornia, A.; Totti, F.; Mannini, M.; Sessoli, R.
abstract

Magnetic materials interfaced with superconductors may reveal new physical phenomena with potential for quantum technologies. The use of molecules as magnetic components has already shown great promise, but the diversity of properties offered by the molecular realm remains largely unexplored. Here we investigate a submonolayer of tetrairon(iii) propeller-shaped single molecule magnets deposited on a superconducting lead surface. This material combination reveals a strong influence of the superconductor on the spin dynamics of the single molecule magnet. It is shown that the superconducting transition to the condensate state switches the single molecule magnet from a blocked magnetization state to a resonant quantum tunnelling regime. Our results open perspectives to control single molecule magnetism via superconductors and to use single molecule magnets as local probes of the superconducting state.

2019 - NON CANONICAL CYCLIC NUCLEOTIDES MONOPHOSPHATES IN APHANIZOMENON FLOS-AQUAE: NUCLEAR MAGNETIC RESONANCE AND MASS SPECTROMETRY [Abstract in Atti di Convegno]
Righi, V.; Zambon, A.; Parenti, F.; Rossi, M. C.; Mucci, A.
abstract

Aphanizomenon os-aquae (AFA) cyanobacteria from Klamath Lake (Oregon) are considered a superfood", due to their complete nutritional prole that has proved to have health-enhancing properties. AFA metabolome is quite complex. Here, we present a study that, combining multinuclear 1H, 31P and 13C NMR spectroscopy and high-resolution mass spectrometry, allows the detection of rather unusual phosphorylated metabolites in AFA. In this study we focused our attention on AFA phosphorylated metabolites giving 31P NMR signals at 20 ppm, a chemical shift that pointed to phosphonates. They instead revealed to be nucleoside 2',3'-cyclic monophosphates (cNMPs), that were characterized by multinuclear 1H, 31P and 13C NMR spectroscopy and high-resolution mass spectrometry. Our data are fully consistent with the proposed structures and hence demonstrate the presence of cNMPs in AFA, for the rst time. The most studied of these biomolecules is cAMP that activates a protective mechanism in the case of brain tissue injury, whereas it inhibits mitophagy of damaged mitochondria in the kidney.

2019 - Non canonical Cyclic Nucleotides Monophosphates in Aphanizomenon flosaquae: nuclear magnetic resonance and mass spectrometry [Poster]
Righi, Valeria; Zambon, Alfonso; Parenti, Francesca; Rossi, Maria Cecilia; Libertini, Emanuela; Mucci, Adele
abstract

Aphanizomenon flos-aquae (AFA) cyanobacteria from Klamath Lake (Oregon) are considered a “superfood”, due to their complete nutritional profile that has proved to have health-enhancing properties. AFA metabolome is quite complex. Here, we present a study that, combining multinuclear 1H, 31P and 13C NMR spectroscopy and high-resolution mass spectrometry, allows the detection of rather unusual phosphorylated metabolites in AFA. In this study we focused our attention on AFA phosphorylated metabolites giving 31P NMR signals at 20 ppm, a chemical shift that pointed to phosphonates. They instead revealed to be nucleoside 2’,3’-cyclic monophosphates (cNMPs), that were characterized by multinuclear 1H, 31P and 13C NMR spectroscopy and high-resolution mass spectrometry. Our data are fully consistent with the proposed structures and hence demonstrate the presence of cNMPs in AFA, for the first time. The most studied of these biomolecules is cAMP that activates a protective mechanism in the case of brain tissue injury, whereas it inhibits mitophagy of damaged mitochondria in the kidney. The role of the other cNMPs there is much to be discovered.

2019 - Non-canonical Cyclic Nucleoside Monophosphates in Aphanizomenon flos-aquae: nuclear magnetic resonance and mass spectrometry [Poster]
Righi, V.; Zambon, A.; Parenti, F.; Rossi, M. C.; Mucci, A.
abstract

Aphanizomenon flos-aquae (AFA) cyanobacteria from Klamath Lake (Oregon) are considered a superfood", due to their complete nutritional prole that has proved to have health-enhancing properties. AFA metabolome is quite complex. Here, we present a study that, combining multinuclear 1H, 31P and 13C NMR spectroscopy and high-resolution mass spectrometry, allows the detection of rather unusual phosphorylated metabolites in AFA [1,2]. In this study we focused our attention on AFA phosphorylated metabolites giving 31P NMR signals at 20 ppm, a chemical shift that pointed to phosphonates. They instead revealed to be nucleoside 2',3'-cyclic monophosphates (cNMPs), that were characterized by multinuclear 1H, 31P and 13C NMR spectroscopy and high-resolution mass spectrometry. Our data are fully consistent with the proposed structures and hence demonstrate the presence of cNMPs in AFA, for the rst time. The most studied of these biomolecules is cAMP that activates a protective mechanism in the case of brain tissue injury, whereas it inhibits mitophagy of damaged mitochondria in the kidney [3]. The role of the other cNMPs there is much to be discovered.

2019 - Nucleoside 2’,3’-cyclic monophosphates in Aphanizomenon flos-aquae detected through nuclear magnetic resonance and mass spectrometry [Articolo su rivista]
Zambon, A.; Righi, V.; Parenti, F.; Libertini, E.; Rossi, M. C.; Mucci, A.
abstract

Aphanizomenon flos-aquae (AFA) cyanobacteria from Klamath Lake (Oregon) are considered a “superfood”, due to their broad nutritional profile that has proved to have health-enhancing properties. AFA metabolome is quite complex. Here, we present a study that, combining multinuclear 1H, 31P and 13C Nuclear Magnetic Resonance (NMR) spectroscopy and high-resolution mass spectrometry, led to the detection of uncommon phosphorylated metabolites in AFA. We focused our attention on 31P NMR signals at 20 ppm, a chemical shift that usually points to the presence of phosphonates. The molecules contributing to 20 ppm 31P NMR signals revealed, instead, to be nucleoside 2’,3’-cyclic monophosphates. These metabolites were fully characterized by multinuclear 1H, 31P and 13C NMR spectroscopy and high-resolution mass spectrometry.

2019 - Optoelectronic Properties of A‐π‐D‐π‐A Thiophene‐Based Materials with a Dithienosilole Core: An Experimental and Theoretical Study [Articolo su rivista]
Parenti, Francesca; Caselli, Monica; Vanossi, Davide; Buffagni, Mirko; Imperato, Manuel; Pigani, Laura; Mucci, Adele
abstract

Two A‐π‐D‐π‐A thiophene based small molecules, with a central dithienosilole core and dicyanovinyl end groups were synthesized. These compounds differ only for the presence of alkyl and alkylsulfanyl chains, respectively, on thiophene beta positions. The computational data together with the spectroscopic and electrochemical findings (obtained by means of absorption, steady‐state/time‐resolved emission techniques and cyclic voltammetry) revealed that both molecules possess low electronic and optical band gaps, broad absorption spectra and a good stability both in p and n‐doping states, properties that make them suitable for optoelectronic applications. In either compounds the HOMO‐LUMO transition involves an intramolecular charge transfer from the electron‐donor dithienosilole unit to the two terminal electron‐acceptor DCV groups. A marked positive emission solvatochromism was observed for both molecules and was interpreted on the basis of the symmetry breaking in the S1 excited state. The two synthesized compounds were also compared to their shorter precursors and to similar oligothiophenes to understand how the nature of the building block influences the characteristics of the final materials. Furthermore, it was possible to better understand the contribution of the sulfur atom in modulating the optical properties of the small molecules studied.

2019 - Potent Anti-Cancer Properties of Phthalimide-Based Curcumin Derivatives on Prostate Tumor Cells [Articolo su rivista]
Belluti, Silvia; Orteca, Giulia; Semeghini, Valentina; Rigillo, Giovanna; Parenti, Francesca; Ferrari, Erika; Imbriano, Carol
abstract

Metastatic castration-resistant prostate cancer is commonly treated with chemotherapy, whose effect is less than satisfactory. This raised the need for novel agents for the treatment of prostate cancer. In the present study, five phthalimide-based curcumin derivatives were synthesized and completely characterized to assess improved stability, pharmacodynamics, and radical scavenging ability. To investigate the potential application in anti-cancer therapy, the anti-proliferative activity of the synthesized molecules was determined on aggressive prostate tumor cells. We demonstrated that the K3F21 derivative has increased potency compared to curcumin, in terms of GI50, anti-proliferative and anti-migrating activities. K3F21 inhibits anchorage-dependent and -independent growth of prostate cancer cells by altering the expression of key genes controlling cell proliferation, such as Cylins D1, B1 and B2, and apoptosis, among which Puma, Noxa, and Bcl-2 family members. Finally, the anti-cancer activity of K3F21 was demonstrated by the analysis of cancer-associated PI3K/AKT, ERK, and p38 signaling pathways.

2018 - Spin-controlled electrochemistry using chiral electrodes: Effects on water electrolysis [Poster]
Tassinari, F.; Mtangi, W.; Banerjee-Ghosh, K.; Adelizzi, B.; Parenti, F.; Vankayala, K.; Palmans, A.; Jentzsch, A. V.; Fontanesi, C.; Mucci, A.; Meijer, E. W.; Naaman, R
abstract

Hydrogen is the ecologically ideal energy vector. Efficient photo-electrochemical production of hydrogen from water could be the optimal solution to the energy storage problems related to renewable sources. However, in the water splitting reaction the electric potential required to initiate the process significantly exceeds the thermodynamic limit. By controlling the spins of the electrons that are transferred from the solution to the anode, and ensuring that they are coaligned, the threshold voltage for the process can in theory be decreased to that of the thermodynamic voltage. In the present study, by using TiO2 anodes coated with chiral materials, we explore what are the effects of having a spin-polarized current on water electrolysis. The spin-polarization arises from exploiting what is known as Chiral Induced Spin Selectivity effect by using chiral molecules as spin filters. When using chiral molecules instead of a non-chiral analogue, the hydrogen production from water is enhanced, the threshold voltage is reduced and the by-product formation of hydrogen peroxide is suppressed. Figure: control of hydrogen peroxide production. UV-vis spectra from the titration of the used electrolyte (Na2SO4) with o-tolidine of bare TiO2 and TiO2 electrodes coated with (A) self-assembled Zn-porphyrins of either achiral (A-Zn) or chiral (S-Zn) and (B) TPyA molecules. (C) When the electrons transfer to the anodes is non spin specific the spins of the unpaired electrons on the two radicals are aligned antiparallel, hence the interaction is on a singlet surface that correlates with the production of hydrogen peroxide (H2O2). (D) When the electron transfer to the anode is spin specific, the spins of the two electrons are aligned parallel to each other, hence the two radicals interact on a triplet surface that forbids the formation of H2O2 and facilitates the production of oxygen in its ground state.

2018 - Spin-controlled electrochemistry using chiral electrodes: Effects on water electrolysis [Abstract in Atti di Convegno]
Tassinari, F; Mtangi, W; Banerjee-Ghosh, K; Adelizzi, B; Parenti, F; Vankayala, K; Palmans, A; Jentzsch, Av; Fontanesi, C; Mucci, A; Meijer, E; Naaman, R
abstract

Hydrogen is the ecologically ideal energy vector. Efficient photo-electrochemical production of hydrogen from water could be the optimal solution to the energy storage problems related to renewable sources. However, in the water splitting reaction the electric potential required to initiate the process significantly exceeds the thermodynamic limit. By controlling the spins of the electrons that are transferred from the solution to the anode, and ensuring that they are coaligned, the threshold voltage for the process can in theory be decreased to that of the thermodynamic voltage. In the present study, by using TiO2 anodes coated with chiral materials, we explore what are the effects of having a spin-polarized current on water electrolysis. The spin-polarization arises from exploiting what is known as Chiral Induced Spin Selectivity effect by using chiral molecules as spin filters. When using chiral molecules instead of a non-chiral analogue, the hydrogen production from water is enhanced, the threshold voltage is reduced and the by-product formation of hydrogen peroxide is suppressed.

2018 - Thiophene based A-D-A small molecules with a dithienosilole core: synthesis, theoretical calculations and optoelectronic properties [Abstract in Atti di Convegno]
Parenti, Francesca; Buffagni, Mirko; Caselli, Monica; Mucci, Adele; Pigani, Laura; Vanossi, Davide; Zambon, Alfonso
abstract

Polythiophenes are conjugated materials finding application in many optoelectronic devices.1 Recently, much attention has been devoted to oligothiophenes, the shorter analogous compounds of these polymers. These semiconductor materials are structurally well-defined, monodisperse, free of defects and often possess higher polarizability and charge mobility with respect to the corresponding polymers.2 Thiophene-based small molecules3 are well studied as photoactive materials in organic solar cells. In particular, molecules with A-π-D-π-A architecture, formed by a central electron donating building block (D) and two terminal electron accepting groups (A) linked by π-conjugated bridges, show a low energy absorption band making them suitable as active layers in organic solar cells.4,5 Little modifications of the backbone, i.e. by changing the length of the alkyl substituents or the type of the functional groups, will often result in remarkable modification of the band gap and other optical properties. Here, we present the theoretical calculations, the synthesis and the characterization of two A-π-D-π-A small molecules E1 and E2, where the central unit is a dithienosilole, the terminal units are methyldicyanovinyl functionalized thiophene rings and the π-bridges are alkyl or alkylsulfanyl functionalized thiophene rings, respectively. The aim of this research is to study the structural, electronic and optical properties of these molecules to better understand the role of the sulfur atom of the alkylsulfanyl chains and to gain insight on the properties of these materials in view of their application in optoelectronic and photovoltaic devices

2017 - Chiral Polythiophenes [Capitolo/Saggio]
Parenti, Francesca; Schenetti, Luisa; Tassinari, Francesco
abstract

This review reports the synthesis and the properties of chiral polythiophenes (PTs) and in particular it is focused on PTs bearing a sulfur atom directly bonded to the thiophene ring. These polymers show remarkable properties, related to their chirality and electrical conductivity and to the ability to interact with chiral molecules opening the possibility for using them in new potential applications, like chiral sensors, chiral resolution and electrodes.

2017 - Enhanced Hydrogen Production with Chiral Conductive Polymer-Based Electrodes [Articolo su rivista]
Tassinari, Francesco; Banerjee Ghosh, Koyel; Parenti, Francesca; Kiran, Vankayala; Mucci, Adele; Naaman, Ron
abstract

Efficient photo-electrochemical production of hydrogen from water is the aim of many studies in recent decades. Typically, one observes that the electric potential required to initiate the process significantly exceeds the thermodynamic limit. It was suggested that by controlling the spins of the electrons that are transferred from the solution to the anode, and ensuring that they are coaligned, the threshold voltage for the process can be decreased to that of the thermodynamic voltage. In the present study, by using anodes coated with chiral conductive polymer, the hydrogen production from water is enhanced, and the threshold voltage is reduced, as compared with anodes coated with achiral polymer. When CdSe quantum dots were embedded within the polymer, the current density was doubled. These new results point to a possible new direction for producing inexpensive, environmentally friendly, efficient water-splitting photo-electrochemical cells. (Graph Presented).

2017 - Novel oligothiophenes with reduced HOMO-LUMO band gap for Optoelectonics [Abstract in Atti di Convegno]
Parenti, Francesca; Buffagni, Mirko; Zambon, Alfonso; Caselli, Monica; Vanossi, Davide; Mucci, Adele
abstract

Here we present the synthesis of A-π-D-π-A thiophene-based oligomers (Figure 1); in the design of these materials we incorporated both electron-donor and electron-acceptor groups by having a central donor dithienosilole, two terminal methyldicyanovinyl acceptor groups and two bithienyl units, functionalised with alkyl or alkylsulfanyl chains, as π-bridges.

2017 - Polymers with Alkylsulfanyl Side Chains for Bulk Heterojunction Solar Cells: Toward a Greener Strategy [Articolo su rivista]
Tassinari, Francesco; Libertini, Emanuela; Parenti, Francesca; Mucci, Adele
abstract

The synthesis and properties of three co-polymers obtained through a Knoevenagel poly-condensation are reported. They are soluble in organic solvents, filmable and solvatochromic. They are characterized through GPC, NMR and UV-visible spectroscopies, CV, and AFM. They display some proneness to form π-stacks, broad absorptions up to about 700 nm, HOMO and LUMO energies that fit those of [60]PCBM. The polymers are incorporated in blends with PCBM within BHJ devices. The best results are found for PSCs obtained from P1 (2.7 % PCE). The insertion of alkylsulfanyl chains improves the photovoltaic performances, with respect to those of alkyl-substituted analogous polymers. The Jsc of the devices are greatly enhanced, supporting the employment of (alkylsulfanyl)thienyl units as base units in photoactive materials.

2017 - Π‑Stacking Signature in NMR Solution Spectra of Thiophene-Based Conjugated Polymers [Articolo su rivista]
Parenti, Francesca; Tassinari, Francesco; Libertini, Emanuela; Lanzi, Massimiliano; Mucci, Adele
abstract

Studies on conjugated polymers seldom report on their NMR characterization in solution. This paper shows how NMR experiments, both 1H NMR and routine 2D NMR spectra, can help in gaining a further insight into the aggregation behavior of conjugated polymers and could be used to flank the more employed solid-state NMR and other spectroscopy and microscopy techniques in the understanding of the aggregation processes. NMR spectroscopy allows distinguishing, within the class of poorly solvatochromic conjugated polymers, those highly prone to form π-stacked aggregates from the ones that have a low tendency toward π-stacking.

2016 - CONJUGATED POLYMERS FOR PHOTOVOLTAICS: FROM SOLUTION TO SOLID-STATE NMR [Abstract in Atti di Convegno]
Mucci, Adele; Parenti, Francesca; Libertini, Emanuela; Tassinari, Francesco; Schenetti, Luisa
abstract

Conjugated polymers are widely studied for applications in organic electronics.[1] The structural scenery is varied and the properties of polymers and copolymers can change heavily with the structure. The characterization of organic polymers used in organic electronics, and in particular in polymer solar cells (PSCs), is strongly multidisciplinary. It requires expertise within different branches of chemistry and at the border among chemistry, physics and engineering. Here, the contribution of solution NMR to the study of self-aggregation properties of thiophene based conjugated polymers will be presented. NMR findings on polymers in solution appear to be correlated to morphological properties and solvatochromism. Since one of the most actively investigated application of conjugated polymers is as donors in bulk hetero junction PSCs, also some results obtained with solid-state NMR on polymer/fullerene blends will be reported.

2016 - Conjugated Polymers for Solar Cells Incorporating the Dithienosilole Unit [Abstract in Atti di Convegno]
Parenti, Francesca; Tassinari, Francesco; Cugini, Alice; Schenetti, Luisa; Morvillo, P.; Ricciardi, R.; Mucci, Adele
abstract

Polymer Solar Cells (PSC) are widely studied as low cost, light weight and flexible alternative to silicon-based solar cells. The polymers suitable for this purpose should possess good solubility and filming properties and extended π-conjugated systems with high absorption coefficients, UV–Vis-NIR spectra ideally matching the solar spectrum, high hole mobility, and HOMO–LUMO energy levels suitable to be coupled with the acceptor species, such as fullerene derivatives. One of the newest monomeric units that can be used to build conjugated polymers for PSC is functionalized dithienosilole. This contribution will deal with the synthesis and properties of two different low band gap copolymers containing dithienosilole alternated to thienothiophene or to substituted bithiophene

2016 - Mycosporine-like Amino Acids and Other Phytochemicals Directly Detected by High-Resolution NMR on Klamath (Aphanizomenon flos-aquae) Blue-Green Algae [Articolo su rivista]
Righi, Valeria; Parenti, Francesca; Schenetti, Luisa; Mucci, Adele
abstract

This study describes for the first time the use of high-resolution nuclear magnetic resonance (NMR) on Klamath (Aphanizomenon flos-aquae, AFA) blue-green algae directly on powder suspension. These algae are considered to be a "superfood", due to their complete nutritional profile that has proved to have important therapeutic effects. The main advantage of NMR spectroscopy is that it permits the detection of a number of metabolites all at once. The Klamath alga metabolome was revealed to be quite complex, and the most peculiar phytochemicals that can be detected directly on algae by NMR are mycosporine-like amino acids (porphyra-334, P334; shinorine, Shi) and low molecular weight glycosides (glyceryl β-d-galactopyranoside, GalpG; glyceryl 6-amino-6-deoxy-α-d-glucopyranoside, ADG), all compounds with a high nutraceutical value. The presence of cis-3,4-DhLys was revealed for the first time. This molecule could be involved in the anticancer properties ascribed to AFA.

2016 - Phytochemicals Directly Detected by High-Resolution NMR on Klamath (Aphanizomenon Flos-Aquae) Blue-Green Algae [Abstract in Atti di Convegno]
Mucci, Adele; Parenti, Francesca; Schenetti, Luisa; Righi, V.
abstract

Aphanizomenon flos-aquae (AFA) is a wild freshwater unicellular microalga that spontaneously grows in copious amounts in Upper Klamath Lake (OR, USA) a volcanic lake with hot, deep and mineral rich waters. These algae are considered as a “superfood”, due to their complete nutritional profile that has proved to have important therapeutic effects.[1-4] Here we report on the results obtained applying high-resolution NMR directly on AFA powder suspension. Klamath algae metabolome revealed to be quite complex. The most peculiar phytochemicals that can be detected directly on algae by NMR are mycosporine-like amino acids and low molecular weight glyceryl glycosides.

2016 - Poly(Cyanovinylene Phenylene-Co-Thiophene)s For Polymer Solar Cells [Abstract in Atti di Convegno]
Tassinari, Francesco; Parenti, Francesca; Di Nicola, F. P.; Ballarin, B.; Lanzi, M.; Libertini, Emanuela; Mucci, Adele
abstract

We synthetized, using a Knoevenagel polycondensation reaction, three different poly(phenylenecyanovinylene-co-thiophenes) , slightly changing the structure of the thiophene comonomer, to study the effect that these changes can have on the efficiency of photovoltaic devices built using these polymers

2016 - Polymers for application in organic solar cells: Bithiophene can work better than thienothiophene when coupled to benzodithiophene [Articolo su rivista]
Parenti, Francesca; Ricciardi, Rosa; Diana, Rosita; Morvillo, Pasquale; Fontanesi, Claudio; Tassinari, Francesco; Schenetti, Luisa; Minarini, Carla; Mucci, Adele
abstract

The synthesis and characterization of two low band gap copolymers (P1 and P2) incorporating benzo[1,2-b:4,5- b’]dithiophene unit substituted with octylsulfanylthienyl groups (OSBT) are here reported. These materials, designed to be employed in polymer solar cells (PSCs), were obtained from alternating OSBT and bithiophene (P1) or thienothiophene (P2) units. Their structural electrochemical and photophysical properties were investigated. They are thermally stable and soluble in organic solvents from which they easily form films. They also form p-stacks in solution, in film and display a moderate solvatochromism. These polymers were tested with [70]PCBM in bulk-heterojunction (BHJ) PSCs where they act as donor materials and [70]PCBM is the electron acceptor. The best device, obtained using a 1:3 weight ratio for the P1:[70]PCBM blend, shows a PCE around 1.5%. A broad response from 350 to 700 nm is also observed in the external quantum efficiency (EQE) curves, wider for P1 with respect to P2.

2015 - Characterization of Conducting Polymers for Organic Solar Cells [Abstract in Atti di Convegno]
Parenti, Francesca; Tassinari, Francesco; Fontanesi, Claudio; Schenetti, Luisa; Morvillo, P.; Ricciardi, R.; Diana, R.; Minarini, C.; Lanzi, M.; Mucci, Adele
abstract

Thiophene based copolymers are widely studied as the donor active layer in bulk hetero junction polymer solar cells (PSCs). These copolymers, in some cases formed by an alternating structure of donor/acceptor units, can be fine tuned in their electronic energy levels in order to achieve better power conversion efficiencies values.1 The characterization of organic polymers for application in PSCs, or organic electronics in general, is multidisciplinary in nature, for it requires expertise within different branches of chemistry and at the border among chemistry, physics and engineering.2 As organic chemists, we have to check the structure and properties of these polymers and this is not always trivial. This contribution will be mainly focussed on the NMR characterization of polymers in solution and to the problems arising when aggregation occurs. This is particularly observed when benzodithiophene and thienothiophene (that are among the most popular units) are present in the backbone. NMR findings appear to be strongly correlated to solvatochromism or morphological properties

2015 - Chiral conductive polymers as spin filters [Abstract in Atti di Convegno]
Tassinari, Francesco; Parenti, Francesca; Mondal, P. C.; Kantor ­‐Uriel, N.; Mathew, S. P.; Naaman, R.; Fontanesi, Claudio; Schenetti, Luisa; Mucci, Adele
abstract

We investigated spin-selective electron transport through poly{[methyl N -(tert-butoxycarbonyl)-S-3- thienyl- L -cysteinate]-cothiophene} (PCT-L)5. Measurements were performed in two configurations: in an electrochemical cell at room temperature or in a solid state device at various temperatures.

2015 - Chiral Polythiophenes [Abstract in Atti di Convegno]
Schenetti, Luisa; Libertini, Emanuela; Mucci, Adele; Parenti, Francesca; Tassinari, Francesco
abstract

Polythiophenes (PT) belong to the class of Conducting organic polymers and Conducting organic polymers that possess chirality present some unique opportunities when used as chiral substrates or as chiral electrode materials. The properties of chiral conducting PT can be tunable modifying the functional groups to the polymer backbone) and since these polymers can be formed as particles, membranes or micro- and nanodimensional fibers ,it is possible to design and to develop specific molecular systems for molecular recognition. The chiroptical properties of CCP films were studied under different evaporation conditions. The chiral recognition abilities of CCP are reported and also a new application in the field of spin filter.

2015 - Crocus sativus Petals: Waste or Valuable Resource? The Answer of High-Resolution and High-Resolution Magic Angle Spinning Nuclear Magnetic Resonance [Articolo su rivista]
Righi, Valeria; Parenti, Francesca; Tugnoli, Vitaliano; Schenetti, Luisa; Mucci, Adele
abstract

Intact Crocus sativus petals were studied for the first time by high-resolution magic angle spinning nuclear magnetic resonance (HR-MAS NMR) spectroscopy, revealing the presence of kinsenoside (2) and goodyeroside A (3), together with 3-hydroxy-γ-butyrolactone (4). These findings were confirmed by HR-NMR analysis of the ethanol extract of fresh petals and showed that, even though carried out rapidly, partial hydrolysis of glucopyranosyloxybutanolides occurs during extraction. On the other hand, kaempferol 3-O-sophoroside (1), which is "NMR-silent" in intact petals, is present in extracts. These results suggest to evaluate the utilization of saffron petals for phytopharmaceutical and nutraceutical purposes to exploit a waste product of massive production of commercial saffron and point to the application of HR-MAS NMR for monitoring bioactive compounds directly on intact petals, avoiding the extraction procedure and the consequent hydrolysis reaction.

2015 - New one-step thiol functionalization procedure for Ni by self-assembled monolayers [Articolo su rivista]
Fontanesi, Claudio; Tassinari, Francesco; Parenti, Francesca; Cohen, Hagai; Mondal, Prakash Chandra; Kiran, Vankayala; Giglia, Angelo; Pasquali, Luca; Naaman, Ron
abstract

This article reports on a facile and fast strategy for the self-assembled monolayer (SAM) functionalization of nickel surfaces, employing cyclic voltammetry (CV) cycling of a suitable tailored solution containing the species to be adsorbed. Results are presented for ultrathin films formed on Ni by 1-hexadecanethiol (C16), L-cysteine (L-cys), and the polymethyl (2R)-3-(2,2'-bithiophen-4-ylsulfanyl)-2-[(tert-butoxycarbonyl)amino]propanoate (PCT-L) thiophene-based chiral polymer. The effective formation of high-quality ultrathin organic films on the nickel was verified both electrochemically and by exploiting typical surface characterization techniques such as contact angle, ellipsometry, atomic force microscopy (AFM), polarization modulation-infrared reflection-absorption spectroscopy (PM-IRRAS), and X-ray photoelectron spectroscopy (XPS).

2015 - Performance of polymer solar cells with (alkylsulfanyl)bithiophene copolymers [Relazione in Atti di Convegno]
Ricciardi, R.; Morvillo, P.; Diana, R.; Minarini, C.; Mucci, Adele; Parenti, Francesca; Tassinari, Francesco; Schenetti, Luisa
abstract

In this work we report the performances of PSCs realized with the following materials as electron donor: a polymer containing (alkylsulfanyl)bithiophene unit, the poly[4,4’- bis(butylsulfanyl)-2,2’-bithiophene] (PolyM), a copolymer having bis(octylsulfanyl)bithienyl (OSBT) unit alternated with a BDT unit substituted with ethylhexyloxyl groups, the poly[4,8-bis(2-ethylhexyloxy)benzo[1,2-b:4,5-b′]dithiophenealt- 4,4’-bis(octylsulfanyl)-2,2’-bithiophene] (PolyS) and a copolymer having OSBT unit alternated with BDT unit substituted with (octylsulfanyl)thienyl groups, the poly{4,8- bis[(5-octylsulfanyl)-2-thienyl]benzo[1,2-b:4,5- b′]dithiophene-alt-4,4’-bis(octylsulfanyl)-2,2’-bithiophene} (PolyA)

2015 - Synthesis Of Low Band-Gap Conjugated Polymers For Application In Solar Cells [Abstract in Atti di Convegno]
Libertini, Emanuela; Morvillo, P.; Mucci, Adele; Tassinari, Francesco; Schenetti, Luisa; Parenti, Francesca
abstract

Polymer solar cells are a fascinating low cost alternative to silicon-based solar cells1 thanks to light weight, mechanical flexibility and processability. The polymers suitable for this purpose should possess good filming and absorption properties (absorption coefficients >105 cm-1 and UV–Vis spectrum ideally matching the solar spectrum)2, high hole mobility, and HOMO–LUMO energy levels suitable to be coupled with the acceptor species3. In this presentation the synthesis of three different low band gap copolymers is reported and discussed. The properties of these materials are compared in order to gain an insight on the molecular structure-performance relationship of the final device

2014 - Low band gap polymers for application in solar cells: synthesis and characterization of thienothiophene-thiophene copolymers [Articolo su rivista]
P., Morvillo; R., Diana; Fontanesi, Claudio; R., Ricciardi; M., Lanzi; Mucci, Adele; Tassinari, Francesco; Schenetti, Luisa; C., Minarini; Parenti, Francesca
abstract

In this paper we present the synthesis and characterization of two novel copolymers obtained from a bithiophene unit carrying octylsulfanyl side chains and thienothiophene units substituted with keto (PK) or ester (PE) groups. Their structural, electrochemical and photophysical properties were investigated by gel permeation chromatography (GPC), thermogravimetric analysis (TGA), NMR, UV-visible-NIR spectroscopy, cyclic voltammetry (CV) and atomic force microscopy (AFM). They possess good solubility in common organic solvents, filmability, proneness to form π-stacks, moderate solvatochromism, good thermal stability and low band gap energy. They were tested as donor materials in combination with [70]PCBM (electron acceptor) in bulk-heterojunction polymer solar cells. The geometry of the devices are: glass/ITO/PEDOT:PSS/ copolymer:[70]PCBM/Ca/Al. The external quantum efficiency curve of the best device, realized using a blend of PK:[70]PCBM, 1:2 weight ratio, shows a broad response from 350 to 1000 nm. The power conversion efficiency under 100 mW/cm2 AM 1.5G illumination is greater than 1%.

2014 - Polymer Solar Cells based on Benzodithiophene copolymers [Abstract in Atti di Convegno]
Parenti, Francesca; Diana, R.; Fontanesi, Claudio; Minarini, C.; Morvillo, P.; Ricciardi, R.; Schenetti, Luisa; Tassinari, Francesco; Mucci, Adele
abstract

Polymer solar cells are widely seen as the promise to a cheap alternative to the silicon-based ones. In addition to their low costs, they also have other advantages such as light weight, easy processability and compatibility with large scale flexible substrates, which make them suitable for a wide range of applications. However, the efficiency of photovoltaic energy conversion for these plastic devices is still low and this is limiting their commercial use. The efficiency of these polymeric photovoltaic cells got a significative increase when the bulk heterojunction (BHJ) configuration was introduced: it consists in an interpenetrating network of electron donor and acceptor materials that largely increases the active area and diminishes the distance that charge carriers have to travel. Recently, benzodithiophene (BDT) based polymers (Fig.1) have been used as electron donors in polymer solar cells showing very promising properties such as an increased charge transport and a red shift on the absorption spectra. In this work, the synthesis of different regioregular copolymers having substituted BDT as one of the monomers are described. The obtained polymers are characterized by spectroscopic and electrochemical techniques. Energy conversion measurements of BHJ solar cells produced with these polymers were conducted, and the electrical performances were compared in order to study the influence of the different comonomers on the overall efficiency of the devices.

2014 - Synthesis and characterization of an organic co-polymer for photovoltaic application [Abstract in Atti di Convegno]
Andrea, Copelli; Tassinari, Francesco; Mucci, Adele; Parenti, Francesca
abstract

Harvesting energy directly from sunlight using photovoltaic technology is considered as being one of the most important ways to address growing global energy needs using a renewable resource. Polymeric solar cells (PSCs) are a promising alternative to silicon-based solar cell for producing clean and renewable energy thanks to light weight, mechanical flexibility, processability and low costs [1]. The most studied polymers are the 3-alkyl substituted polythiophenes, but they show limited efficiency and, to improve power conversion, the synthesis of new systems is required [2]. Co-polymers formed by ThienoThiophene Carboxylate (TTC) and DiThienoSilole (DTS) units are widely studied as Donor systems in Bulk Heterojunction (BHJ) solar cells. In this presentation we report the synthesis of PSiTT (see the chemical structure) and it's characterization via UV-Vis-NIR, NMR Spectroscopy, IR, AFM and GPC.

2014 - Synthesis of low bandgap Thiophene-Based Copolymers: new donor material candidates in organic solar cells [Abstract in Atti di Convegno]
Parenti, Francesca; P., Morvillo; R., Diana; R., Ricciardi; C., Minarini; Fontanesi, Claudio; Mucci, Adele; A., Copelli; Schenetti, Luisa; Tassinari, Francesco
abstract

Polymer solar cells (PSCs) are emerging as promising alternatives to silicon-based solar cells [1] thanks to light weight, mechanical flexibility, processability and low costs. One of the common polymers used in PSCs are 3-alkyl substituted polythiophenes, but a low band gap alternative is needed in order to reach better cell performances [2]. Copolymers bearing thienothiophene (TT) and benzodithiophene (BDT) alternating units are widely studied as donor material in Bulk Heterojunction Cells [3]. In this poster communication we report on the synthesis and spectroscopic electrochemical, photovoltaic characterization of two thiophene based copolymers bearing thienyl substituted-BDT units alternating with bithiophene and TT-units respectively.

2013 - Citron and lemon under the lens of HR-MAS NMR spectroscopy [Articolo su rivista]
Mucci, Adele; Parenti, Francesca; Valeria, Righi; Schenetti, Luisa
abstract

High Resolution Magic Angle Spinning (HR-MAS) is an NMR technique that can be applied to semi-solid samples. Flavedo, albedo, pulp, seeds, and oil gland content of lemon and citron were studied through HR-MAS NMR spectroscopy, that was used directly on intact tissue specimens without any physicochemical manipulation. HR-MAS NMR proves to be very immediate in detecting terpenes, sugars, organic acids, aminoacids and osmolites. It is valuable in observing changes in sugars, principal organic acids (mainly citric and malic) and ethanol contents on pulp specimens and this strongly point to its use to follow fruit ripening, or commercial assessment of fruit maturity. HR-MAS NMR was also used to derive the molar percentage of fatty acid components of lipids in seeds, which can change depending on Citrus species and varieties. Finally, this technique was employed to elucidate the metabolic profile of mold flavedo.

2013 - Electrochemically assisted grafting of asymmetric alkynyl(aryl)iodonium salts on glassy carbon with focus on the alkynyl/aryl grafting ratio [Articolo su rivista]
Florini, Nicola; M., Michelazzi; Parenti, Francesca; Mucci, Adele; Sola, Marco; C., Baratti; De Renzi, Valentina; K., Daasbjerg; S. U., Pedersen; Fontanesi, Claudio
abstract

Glassy carbon (GC) surfaces are functionalized exploiting the electrochemical reduction of asymmetric iodonium salts of the general formula [4-Zsingle bondC6H4single bondI+single bondCtriple bond; length of mdashC(CH2)4Cl, Z = NO2, Br, F, H, or CH3]. The range of Z groups was selected aiming to examine the Carylsingle bondI bond energy as a function of the “electron withdrawing/electron donating” ability of the Z-group, with the ultimate purpose of controlling the alkynyl/aryl grafting ratio. The electroreduction mechanism and the characteristics of the grafted surface are studied by means of cyclic voltammetry and X-ray photoelectron spectroscopy. It is shown that the alkynyl/aryl grafting ratio decreases with the increasing electron withdrawing nature of Z, which induces a weakening of the Carylsingle bondI bond. Ab initio DFT vertical electron affinities (EAv) allowed to rationalize the electroreduction potentials of both the bulk and surface functionalised redox couples. Moreover, the alkynyl/aryl grafting ratio is assessed, at a molecular level, on the basis of ab initio DFT potential energy surfaces.

2013 - Regiochemistry in the electrochemical assisted grafting of glassy carbon. With focus on sterical hindrance of lateral chains in the electroreduction process of multi-functionalized bithiophene [Articolo su rivista]
Tassinari, Francesco; Vanossi, Davide; Mucci, Adele; Parenti, Francesca; Fontanesi, Claudio
abstract

The electrochemically assisted grafting process of glassy carbon (GC) surfaces is pursued by using the 7-[(5,50-diiodo-2,20-bithiophen-4-yl)sulfanyl]heptanenitrile (DIBHN). Which is an ad hoc synthesized bithiophene derivative: the DIBHN features two non-equivalent iodine substituents in the 5 (which is under the sterical hindrance of the sulfanylheptanenitrile group) and 50 positions. CV measurements show the occurrence of two reduction processes, the second, more cathodic one, induces the grafting. This result is in qualitative agreement with theoretical calculations (B3LYP/6-311G level of the theory) concerning the comparison of the optimized structures of the DIBHN neutral and radical anion species (first electroreduction process): the C–I bond length of the iodine in the 5 position varies from 2.098 (neutral) to 2.835 Å (radical anion), while the C–I bond length of the iodine in the 50 position remains virtually unchanged when comparing the geometries of the neutral and radical anion structures. Raman spectra are recorded for various polymer film thicknesses; the comparison with theoretical calculated Raman spectra further support the effective grafting of the glassy carbon surface.

2012 - A nanogap–array platform for testing the optically modulated conduction of gold–octithiophene–gold junction for molecular optoelectronics [Articolo su rivista]
Ismael, Rattalino; Valentina, Cauda; Paolo, Motto; Tania, Limongi; Gobind, Das; Luca, Razzari; Parenti, Francesca; Enzo Di, Fabrizio; Mucci, Adele; Schenetti, Luisa; Gianluca, Piccinini; Danilo, Demarchi
abstract

This paper presents a fully–customized platform for the self–assembling and the electric and spectroscopic testing the light dependent conduction of gold–oligothiophene–gold molecular junctions. The flexibility and novelty of the platform rely on its plug-and-play connection to an external electronic board to perform eight parallel nanogap fabrication by Electromigration Induced Break Junction (EIBJ) and molecular electrical characterization. In addition, the octithiophene molecules are ad-hoc synthesized to efficiently self-assembly and selectively bridge the nanogap electrodes upon deposition, which can be carried out directly and in parallel on the 8 nanogap array platform. The high portability of the platform is well suited for in–situ microscopic and spectroscopic analyses. In particular, we tested the electrical functionality of octithiophene molecular junctions, by coupling electrical current–voltage (I–V) characterization with fluorescence and Raman spectroscopies. In addition, Surface–Enhanced Raman Spectroscopy (SERS) was used for the first time to precisely correlate the position of the molecule with the conductance of the junction. Modulation of the electric conductance can be also achieved by varying the light excitation wavelength. Such electrical transduction of the junction revealed a peak in molecule conduction around light excitation wavelength of 450 nm, with a photoresponsive modulation of the current at low bias voltage up to 120% with respect to the initial value at 300 nm. The proposed ad-hoc platform design makes molecular junctions real working blocks, which can be interfaced with external circuitries to serve the function of electronic components or sensors and overcome the limitations of usability, cost and portability of traditional molecular contacting methods, such as Mechanically Controlled Break Junction (MCBJ) or scanning probe microscopy. We thus demonstrate that the optoelectronic properties of oligothiophenes can be exploited in the form of molecular junctions to fabricate optoelectronic devices for molecular electronics.

2012 - A novel copolymer from benzodithiophene and alkylsulfanyl-bithiophene: Synthesis, characterization and application in polymer solar cells [Articolo su rivista]
P., Morvillo; Parenti, Francesca; R., Diana; Fontanesi, Claudio; Mucci, Adele; Tassinari, Francesco; Schenetti, Luisa
abstract

In this paper we present the synthesis and characterization of a novel copolymer from thienothiophene and bithiophene units carrying nonanoyl and octylsulfanyl side chains, poly[1-(thieno[3,4-b]thien-2-yl)nonan-1-one-alt-4,4’-bis(octylsulfanyl)-2,2’-bithiophene] (PolyH). The structural, electrochemical and photophysical properties of PolyH were investigated by gel permeation chromatography (GPC), thermogravimetric analysis (TGA), NMR, UV-VIS-NIR spectroscopy and cyclic voltammetry (CV). PolyH possesses good solubility in common organic solvents, filmability, a proneness to form π-stacks and a moderate solvatochromism. PolyH was tested as donor material in combination with [70]PCBM (electron acceptor) in bulk-heterojunction polymer solar cells. The geometry of the device is: glass/ITO/PEDOT:PSS/ PolyH:[70]PCBM/Ca/Al. The external quantum efficiency curve of the best device (realized using a blend of PolyH:[70]PCBM, 1:2 weight ratio) shows a broad response from 350 to 1000 nm. The power conversion efficiency under 100 mW/cm2 AM 1.5G illumination is greater than 1%.

2012 - Aggregation behaviour of a water-soluble ammonium-functionalizedpolythiophene: Luminescence enhancement induced by bile-acid anions [Articolo su rivista]
R., Cagnoli; Caselli, Monica; Libertini, Emanuela; Mucci, Adele; Parenti, Francesca; Ponterini, Glauco; Schenetti, Luisa
abstract

The water-soluble poly{trimethyl-[7-(3-thienylsulfanyl)heptyl]ammonium iodide-co-thiophene} (PTNDMe3) forms aggregates whose size span a large range of values, depending on solvent, concentrationand film formation conditions. Larger aggregates were detected by atomic force microscopy and dynamic light scattering, smaller ones by DOSY NMR, UVevisible and fluorescence. All techniques indicate a reduced aggregation of PTNDMe3 in DMSO relative to water and a marked de-aggregation of PTNDMe3 in water following addition of bile-acid anions such as deoxycholate and ursodeoxycholate.The latter effect shows itself through a very large enhancement of the polymer photoluminescence likely caused by disruption of aggregated non-emissive exciton traps. A tailored combination of electrostaticand hydrophobic interactions between the polymer and the bile-acid anions seems to be necessary to achieve this effect. These observations suggest that this polythiophene might provide a basis for the development of fluorescent sensors suitable for the detection of medium-sized amphiphilic biomolecules.

2012 - Functionalization of glassy carbon surface by means of aliphatic and aromatic amino acids. An experimental and theoretical integrated approach [Articolo su rivista]
Vanossi, Davide; Benassi, Rois; Parenti, Francesca; Tassinari, Francesco; Giovanardi, Roberto; Florini, Nicola; DE RENZI, Valentina; Arnaud, Gaelle Francoise; Fontanesi, Claudio
abstract

Glassy Carbon (GC) electrode surfaces are functionalized through electrochemical assisted grafting, in oxidation regime, of six amino acids (AA): -Alanine (-Ala), L-Aspartic acid (Asp), 11-aminoundecanoic acid (UA), 4-Aminobenzoic acid (PABA), 4-(4-Amino-phenyl)-butyric acid (PFB), 3-(4-Amino-phenyl)-propionic acid (PFP). Thus, a GC/AA interface is produced featuring carboxylic groups facing the solution. Electrochemical (cyclic voltammetry and electrochemical impedance spectroscopy) and XPS techniques are used to experimentally characterize the grafting process and the surface state. The theoretical results are compared with the experimental evidence to determine, at a molecular level, the overall grafting mechanism. Ionization Potentials, Standard Oxidation Potentials, HOMO and electron spin distributions are calculated at the CCD/6-31G* level of the theory. The comparison of experimental and theoretical data suggests that the main electroactive species is the “zwitterionic” form for the three aliphatic amino acids, while the amino acids featuring the amino group bound to the phenyl aromatic moiety show a different behaviour. The comparison between experimental and theoretical results suggests that both the neutral and zwitterionic forms are present in the acetonitrile solution in the case of 4-(4-Amino-phenyl)-butyric acid (PFB) and 3-(4-Amino-phenyl)-propionic acid.

2012 - HR-MAS NMR of fruits of plants belonging to the Rutaceae family [Abstract in Atti di Convegno]
Mucci, Adele; Parenti, Francesca; V., Righi; Schenetti, Luisa
abstract

Citrus, as one of the worldwide favourite fruits, draws more attention recently due to its therapeutic potentials. In animal models, d-limonene and structural analogues have demonstrated strong chemopreventive effects in lymphomas, mammary, gastric, liver, and lung cancers. [P.L. Crowell, M.N. Gould, Crit. Rev. Oncog. 5, 1, 1994] Limonoids, citrus secondary metabolites, seem to have multiple bioactive functions, including anticancer, reducing cholesterol, anti-anxiety, antimicrobial, and antiviral activities. [G. D. Manners, J. Agric. Food Chem. 2007, 55, 8285.] This is a HR-MAS NMR study on samples from exocarp, mesocarp, endocarp and seeds of Citrus Medica and Citrus Limon fruits aimed at to the evaluation of the potentialities of the technique in the detection and identification of terpenes in different parts of the fruit.1D (water-presaturated, spin-echo and diffusion-filtered spectra) as well as 2D NMR experiments (COSY, TOCSY and HSQC) are carried out at 4 °C on different regions of the commercial fruit cut in pieces that can fit the HR-MAS 4 mm rotor and directly put into it. Attempts at gaining some insight into the dimensions of oil bodies in the flavedo through diffusion experiments will be also presented.

2012 - Low band gap thienothiophene-thiophene copolymer: synthesis, characterization and application in polymer solar cells [Abstract in Atti di Convegno]
P., Morvillo; Parenti, Francesca; R., Diana; Fontanesi, Claudio; M., Lanzi; Mucci, Adele; Tassinari, Francesco; Schenetti, Luisa
abstract

Polymer solar cells (PSCs) have recently attracted considerable attention due to their advantages of low cost, light weight, processability and compatibility with large scale flexible substrates. The most efficient device architecture of polymer solar cells is based on the bulk heterojunction concept in which the active layer, sandwiched between two electrodes with different work functions, consists of a blend of electron donating material, e.g. a p-type conjugated polymer, and an electron accepting material (n-type), such as fullerene derivatives.Polythiophenes are quite interesting materials for this purpose, combining the above described advantages with an enhanced photochemical stability, compared with poly(p-phenylene vinylene) and poly p-phenylene. In this work the synthesis, the spectroscopic and photovoltaic characterization of a thienothiophene-thiophene copolymer are reported. Poly[2-nonanoylthieno[3,4-b]thiophene-4,6-diyl-alt-4,4’-bis(octylsulfanyl)-2,2’-bithiophene]) was obtained by Stille coupling between the dibromo derivative of 2-nonanoylthienothiophene and a distannyl derivative of bis(octylsulfanyl)bithiophene.Bulk heterojunction solar cells using these polymers as donor materials blended with PCBM as acceptor were prepared and investigated. The geometry of the device is: glass/ITO/PEDOT:PSS/Polymer:PCBM/Ca/Al. An efficient charge transfer between the donor and PCBM takes place and the best device obtained has and efficiency of 1% under simulated light (AM1.5G). Further improvement of the efficiency using different acceptors, optimizing layer thickness and lowering polymer impurities can be envisaged.

2012 - Low Bandgap Copolymers with (Alkylsulfanyl) Bithiophene Unit for Efficient Polymer Solar Cells [Relazione in Atti di Convegno]
P., Morvillo; Parenti, Francesca; R., Diana; E., Bobeico; Mucci, Adele; Tassinari, Francesco; Schenetti, Luisa; C., Minarini
abstract

Polymer solar cells have evolved as a promising cost-effective alternative to silicon-based ones. However, low efficiency of these plastic devices limits their feasibility for commercial use. The efficiencies of polymer photovoltaic cells got a major boost with the introduction of the bulk heterojunction (BHJ) configuration consisting of an interpenetrating network of electron donor and acceptor materials. Recently, benzodithiophene based polymers has been used as electron donors in polymer solar cells showing very promising properties such as an increasing charge transport and a red shift of the absorption spectra. In this work the synthesis, the spectroscopic and photovoltaic characterization of a copolymer based on (octylsulfanyl)bithiophene and benzo[1,2-b:4,5-b’]dithiophene units and a polymer based on (butylsulfanyl)bithiophene unit are reported. BHJ solar cells using these polymers as donor materials blended with [70]PCBM as acceptor were prepared and investigated. The geometry of the device is: glass/ITO/PEDOT:PSS/blend/Ca/Al. The electrical performances of the cells were compared in order to study the influence of the benzodithiophene unit on the polymer backbone. The power conversion efficiency of the best realized polymer solar cell is 2.3% under 100 mW/cm2 AM 1.5G illumination

2011 - (Alkylsulfanyl)bithiophene-alt-Fluorene: π-Conjugated Polymers for Organic Solar Cells [Articolo su rivista]
Parenti, Francesca; Pasquale, Morvillo; Eugenia, Bobeico; Rosita, Diana; Massimiliano, Lanzi; Fontanesi, Claudio; Tassinari, Francesco; Schenetti, Luisa; Mucci, Adele
abstract

We describe the synthesis of alternating bithiophene–fluorenecopolymers (P1–P3) with different regiochemistry of thebithienyl unit and different alkylsulfanyl chain lengths. Thestructural, electrochemical and photophysical properties ofthese polymers were investigated by gel permeationchromatography (GPC), differential scanning calorimetry(DSC), NMR, UV/Vis and photoluminescence (PL) spectroscopyand cyclic voltammetry (CV), and the polymerswere used to assemble organic solar cells (OSCs), in combi-IntroductionOrganic conjugated materials are attracting increased attentiondue to their potential in the fields of chemical sensors,[1] electroluminescent devices,[1c,2] field-effect transistors[3] and OSCs.[4] The last is one of the most appealingapplications of conjugated polymers because they have thepotential to be a low cost alternative to conventional inorganicsemiconductors.[5] The major desirable features ofOSCs are mechanical flexibility, very high speed of processingand low cost for large area fabrication.[6] The mostefficient device architecture of polymeric solar cells is basedon the bulk heterojunction concept (BHJ),[7] in which theactive layer, sandwiched between two electrodes with differentwork functions, consists of a blend of electron donatingmaterial, e.g. a p-type conjugated polymer, and an electronaccepting material (n-type), such as fullerene derivatives.For application in OSCs, conjugated polymers should[a] Dipartimento di Chimica, Università di Modena e ReggioEmilia,Via G. Campi 183, 41125 Modena, ItalyFax: +39-059373543E-mail: adele.mucci@unimore.it[b] ENEA, C.R. Portici,Piazzale E. Fermi 1, 80055 Portici (NA), ItalyE-mail: pasquale.morvillo@enea.it[c] Dipartimento di Chimica Industriale e dei Materiali, Universitàdi Bologna,V.le del Risorgimento 4, 40136 Bologna, ItalySupporting information for this article is available on theWWW under http://dx.doi.org/10.1002/ejoc.201100738.Eur. J. Org. Chem. 0000, 0–0 © 0000 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim 1nation with the fullerene derivative methyl [6,6]-phenyl-C61-butyrate (PCBM). P3, with a head-to-head bithienyl unit,shows a broader absorption and a lower band gap with respectto P1 and P2, which have tail-to-tail bithienyl units.The PL intensity of P1–P3 is dramatically quenched in thepresence of PCBM, demonstrating that an efficient chargetransfer between donor and acceptor occurs. The best OSCdevice was obtained with P3.

2011 - Organic Materials for Phovoltaics: Synthesis and Electrochemical Behaviour of a Thiophene Based Copolymer [Abstract in Atti di Convegno]
Parenti, Francesca; R., Diana; Fontanesi, Claudio; P., Morvillo; Mucci, Adele; Schenetti, Luisa; Tassinari, Francesco
abstract

Polymer solar cells (PSCs) have recently attracted considerable attention due to their advantages of low cost, light weight, processability and compatibility with large scale flexible substrates [1]. Polythiophenes are quite interesting materials for this purpose, combining the above described advantages with an enhanced photochemical stability, compared with poly(p-phenylene vinylene) and poly p-phenylene.In this communication the synthesis, the spectroscopic, the electrochemical and photovoltaic characterization of a thiophene based copolymerare reported. The synthesis was performed in analogy to ref. [2] via Stille coupling of a brominated and a stannilated comonomer as illustrated in Fig.1. The copolymer was characterised through 1H and 13C NMR, Uv-Vis spectroscopy, Cyclic Voltammetry.References[1] S. Gunes, H. Neugebauer, N. S. Sariciftci, “Conjugated Polymer-Based Organic Solar Cells” Chem. Rev. 107, 1324 (2007) ; M. Helgesen, R. Søndergaard, F. C. Krebs, “Advanced materials and processes for polymer solar cell devices”, J. Mater. Chem. 20, 36 (2010) ; J. Peet, J. Y. Kim, N. E. Coates, W. L. Ma, D. Moses, A. J. Heeger, G. C. Bazan, “Efficiency enhancement in low-bandgap polymer solar cells by processing with alkane dithiols”, Nat. Mater. 6, 497 (2007) ; S. A. Gevorgyan and F. C. Krebs in Handbook of thiophene-Based materials, I. F. Perepichka and D. F. Perepichka ed. (John Wiley and Sons Ltd., 2009). [2]Yongye Liang, Danqin Feng, Yue Wu, Szu-Ting Tsai, Gang Li, Claire Ray and Luping Yu, “Highly Efficient Solar Cell Polymers Developed via Fine-Tuning of Structural and Electronic Properties”, JACS 131, 7792-7799 (2009)

2011 - Preparation and characterization of bithiophene modified Si(1,1,1) electrodes [Abstract in Atti di Convegno]
Tassinari, Francesco; Fontanesi, Claudio; Mucci, Adele; Parenti, Francesca; Schenetti, Luisa
abstract

The purpose of this work is to prepare a substituted oligothiophene (OT) modified electrode, in which the oligomer is capable of acting as a conductive wire between the electrode surface and the solution bulk.A simple model system is represented by a bithiophene chemically grafted to the surface of a hydrogen terminated n-doped Si(111) electrode. The possibility to functionalize with different moieties the lateral chain and the thiophene rings makes these systems very versatile and easily customizable.

2010 - Experimental and Theoretical Study of the p- and n-Doped States of Alkylsulfanyl Octithiophenes [Articolo su rivista]
C., Bruno; F., Paolucci; M., Marcaccio; Benassi, Rois; Fontanesi, Claudio; Mucci, Adele; Parenti, Francesca; L., Preti; Schenetti, Luisa; Vanossi, Davide
abstract

The charge-transfer and spectral properties of two octithiophenes, namely 4′,4′′′,3′v,3v′-tetra(octylsulfanyl)-2,2′:5′,2′′:5′′,2′′′:5′′′,2′v:5′v,2v:5v,2v′:5v′,2v′′-octithiophene and 4,3′′,4v,4v′′-tetrabromo-4′,4′′′,3′v,3v′-tetra[(R)-2-methylbutylsulfanyl]-2,2′:5′,2′′:5′′,2′′′:5′′′,2′v:5′v,2v:5v,2v′:5v′,2v′′-octithiophene, OT1 and OT2, respectively,are characterized by cyclic voltammetry and spectroelectrochemistry under ultradry conditions. The analysisof the voltammetric results shows the formation of up to the dication for both OT1 and OT2 and up to thetetraanion (OT1) and trianion (OT2) anions. The optical properties of the OT1 (2+, 1+, neutral, 1-, 2-)species were probed by in situ UV-vis-NIR spectroelectrochemistry. The calculated standard potentials atthe B3LYP/cc-pVTZ level of the theory allowed the rationalization of the experimental electrochemical results.The UV-vis-NIR spectra were successfully compared with the theoretical electronic transitions and oscillatorstrength data obtained by time-dependent B3LYP/6-31G* calculations. Theoretical redox potentials and opticaltransitions properties are calculated including “the solvent effect” within the CPCM model. The consistencyobtained between experimental and theoretical results indicates the existence of the hypothesized high-spin/high-charge p- and n-doped electronic states for the OT1 and OT2 octithiophenes here studied.

2010 - Interaction studies of a β-cysteine functionalized polythiophene with biomolecules [Abstract in Atti di Convegno]
Bortolotti, Carlo Augusto; F., Filace; Parenti, Francesca; Mucci, Adele; Schenetti, Luisa
abstract

Polythiophenes are an important representative class of conjugated and thermally stable polymers that can be used in alternative to inorganic semiconductors in optical and electronic devices [1]. Recently, they have been studied as biological sensors [2], thanks to the presence of the electroconducting backbone together with β-substituents able to interact with biological species. The interaction between the polymer side chain functionalities and the analyte can be of different type (hydrogen bonds, ionic interactions …) depending on the analyte, or the backbone itself can directly interact with the biomolecule through π-π stacking.In this study, a previously synthesized β-cysteine functionalized polythiophene (PTCys, Fig 1) [3] was investigated as folic acid [4] and cytochrome C (horse heart) biosensor.[1] Skotheim Ed. T., Reynolds J., Elsenbamer R., Dekker Marcel, Inc., New York, NY, USA, Handbook of conducting polymers 2nd Edition, 1998; Skotheim Ed. T., Dekker Marcel, Inc., New York, NY, USA, Handbook of conducting polymers 1986[2] Berggren, M.; Inganas, O.; Gustafsson, G.; Nature,1994, 372, 444-446[3] Cagnoli R., Lanzi M., Mucci A., Parenti F., Schenetti L., Polymer, 2005, 46(11), 3588-3596[4] Zhiyi Yao, Chun Li and Gaoquan Shi, Langmuir,2008, 24, 12829-12835

2010 - Octithiophenes via One-Pot Oxidative Coupling of 4-(ω-Functionalized Alkylsulfanyl)-2,2′-Bithiophenes [Articolo su rivista]
L., Preti; R., Cagnoli; Parenti, Francesca; M., Lanzi; Libertini, Emanuela; Pinetti, Diego; Schenetti, Luisa; Mucci, Adele
abstract

The oxidative coupling reaction with FeCl3 on nitrile, methyl ester and amino functionalized 4-(alkylsulfanyl)-2,2’-bitiophenes afforded symmetric octithiophenes (OTs). These new OTs have solvatochromic properties similar to those reported for poly(ω-functionalized alkylsulfanyl)thiophenes and have a potential use in optoelectronic devices. The carboxy (obtained through hydrolysis from nitrile and methyl ester functionalized OTs) and the amino functionalized OTs are also water soluble as salts. From this and our previous results, the oxidative coupling with FeCl3 can be proposed as a general method for the synthesis of OTs when the starting materials are 4-(alkylsulfanyl)-, 4-(ω-functionalized alkylsulfanyl)-, and 4-alkylsulfanyl-4’-halo-2,2’-bithiophenes.

2010 - On the Electroreduction Mechanism of Iodonium Salts on Glassy Carbon Electrodes" [Abstract in Atti di Convegno]
K., Daasbjerg; S. U., Pedersen; Florini, Nicola; Parenti, Francesca; Bortolotti, Carlo Augusto; Vanossi, Davide; Fontanesi, Claudio
abstract

Glassy carbon (GC) surfaces can be functionalized exploiting the electrochemical reduction of iodonium salts of general formula [RIR’]+ [1]. The overall mechanism could be roughly sketched as: IR’ bond cleavage:[RIR’]+ + e + GC  R’GC + IR Route (1) IR bond cleavage:[RIR’]+ + e + GC  RGC + IR’ Route (2) Upon electroreduction the I-R or the I-R’ bond dissociate, leading to a neutral closed shell organic iodide and an open shell radical, the latter reacts with the GC electrode (grafting). Several factors can influence the R/R’ ratio grafted on the GC surface. In fact, different amounts of the R and R’ radicals can be formed depending on the electronic structure of the neutral open shell [R-I-R’] • radical. Moreover, the different radicals can exhibit different reactivity toward the carbon surface, as well as different electrochemical stabilities (the radical itself could be reduced to a negative closed shell form). To clarify the interplay of the various factors affecting the final surface functionalization, a number of iodoniums has been considered and experimental evidences (electrochemical and XPS) are compared with theoretical results calculated at the DFT level of the theory (electron affinities, potential energy surfaces of competitive reaction pathways).

2010 - On the electroreduction mechanism of iodonium salts on glassy carbon electrodes [Abstract in Atti di Convegno]
K., Daasbjerg; S. U., Pedersen; DE RENZI, Valentina; Florini, Nicola; Parenti, Francesca; Bortolotti, Carlo Augusto; Vanossi, Davide; Fontanesi, Claudio
abstract

Glassy carbon (GC) surfaces can be functionalized exploiting the electrochemical reduction of iodonium salts of general formula [RIR’]+ [1]. The overall mechanism could be roughly sketched as: IR’ bond cleavage: [RIR’]+ + e + GC  R’GC + IR Route (1) IR bond cleavage: [RIR’]+ + e + GC  RGC + IR’ Route (2) Upon electroreduction the I-R or the I-R’ bond dissociate, leading to a neutral closed shell organic iodide and an open shell radical, the latter reacts with the GC electrode (grafting). Several factors can influence the R/R’ ratio grafted on the GC surface. In fact, different amounts of the R and R’ radicals can be formed depending on the electronic structure of the neutral open shell [R-I-R’] • radical. Moreover, the different radicals can exhibit different reactivity toward the carbon surface, as well as different electrochemical stabilities (the radical itself could be reduced to a negative closed shell form). To clarify the interplay of the various factors affecting the final surface functionalization, a number of iodoniums has been considered and experimental evidences (electrochemical and XPS) are compared with theoretical results calculated at the DFT level of the theory (electron affinities, potential energy surfaces of competitive reaction pathways).

2010 - Study of the metal complexation-ability of Nitrile functionalised oligo and polythiophenes: synthesis and study of the metal complexation-ability [Abstract in Atti di Convegno]
Parenti, Francesca; Fontanesi, Claudio; Schenetti, Luisa; Mucci, Adele
abstract

The synthesis and the complexation properties of some β-sulfanylheptanenitrile functionalised oligo- and polythiophenes reported are studied. The ability of these polymers towards the complexation of different transition metals is compared, in order to get insight into the influence of the substitution density and of the conjugation length on the chelating skills. The complexation-ability is a crucial property in view of possible applications of these materials as chemical sensors for metal ions detection1 or as carbon substitute materials for catalyst support for oxygen reduction or methanol oxidation in direct methanol fuel cells2 (DMFC).References:1) J. Maiti, B. Pokhrel, R. Boruah, S.K.Dolui, Sensors and Actuators B: Chemical 2009, 141,447-451; A.Pietrangelo, M. N. Roberts, M. J. MacLachlan, M.O.Wolf, Polymer Preprints 2009, 50, 280.2) M. Saito, H. Shiroishi, C.to Onoa, S. Tsuzuki, T. Okadaa, Y. Uchimoto, Journal of Molecular Catalysis A: Chemical 2006, 248, 99–108; R. P. Kingsborough, T. M. Swager, Chemistry of Materials 2000, 12, 872-874.

2009 - Electrostatic layer-by-layer construction and characterization of photoelectrochemical solar cells based on water soluble polythiophenes and carbon nanotubes [Articolo su rivista]
V., Sgobba; A., Troeger; Cagnoli, Rita; A., Mateo Alonso; M., Prato; Parenti, Francesca; Mucci, Adele; Schenetti, Luisa; D. M., Guldi
abstract

Positively and negatively charged functionalized polythiophenes and single walled carbon nanotubes were sequentially adsorbed on indium tin oxide electrodes by electrostatic and van der Waalsinteractions using the layer-by-layer deposition method. The resulting donor/acceptor photoelectrodes were tested as photoelectrochemical cells. Upon illumination, monochromatic incident photoconversion efficiencies of 8.2 and 4.3% were determined for eight stacks of single walled carbon nanotubes with ammonium and sulfonate polythiophene derivatives, respectively.

2009 - Electrostatic LbL construction and characterization of photoelectrochemical solar cells based on water soluble polythiophenes and carbon nanotubes [Relazione in Atti di Convegno]
V., Sgobba; A., Troeger; A., Mateo Alonso; M., Prato; Parenti, Francesca; Cagnoli, Rita; Mucci, Adele; Schenetti, Luisa; D. M., Guldi
abstract

Positively and negatively charged functionalized polythiophenes and single walled carbon nanotubes (SWNT) were sequentially adsorbed on indium tin oxide (ITO) electrodes by electrostatic and van der Waals interactions using the layer by layer (LbL) deposition method. Optical, microscopic and spectroelectrochemical properties of mono and multistacks of SWCNT and PT polyelectrolyte containing sulfonate (1) and ammonium (2) side groups, were investigated. Upon illumination, monochromatic incident photoconversion efficiencies of 8.2 and 4.3 % were determined for eight stacks of single walled carbon nanotubes with ammonium and sulphonate polythiophene derivatives, respectively.

2009 - Experimental and theoretical investigation of the p- and n-doped states of alkylsulfanyl octithiophenes [Abstract in Atti di Convegno]
Fontanesi, Claudio; C., Bruno; M., Marcaccio; F., Paolucci; Benassi, Rois; Bortolotti, Carlo Augusto; Mucci, Adele; Parenti, Francesca; Preti, Lisa; Schenetti, Luisa
abstract

We characterizad the charge-transfer properties of two octithiophenes by means of cylcic voltammetry, UV-Vis-NIR spectroelectrochemistry and DFT calculations.

2009 - Experimental and theoretical investigation of the p- and n-doped states of alkylsulfanyl octithiophenes [Abstract in Atti di Convegno]
Fontanesi, Claudio; C., Bruno; M., Marcaccio; F., Paolucci; Benassi, Rois; Bortolotti, Carlo Augusto; Mucci, Adele; Parenti, Francesca; Preti, Lisa; Schenetti, Luisa
abstract

Thiophene based materials, oligothiophenes as well, are promising candidates for technological applications, being a possible alternative to high-cost traditional materials for electronics such as silicon. Thus, in this work the charge-transfer properties oftwo structurally related (Si and S2 as sketched on the left) octithiophenes are studied by means of cyclic voltammetryr”(CV). Digital simulations of CV data ,I— , suggest the reversible formation of up to the dication, for both Si and S2, andup to the 4- (Si) and 3- (S2) anions. The ‘ ‘electronic structure of the Si species (2+, i+, neutral, 1-, 2-) is probed by UV/Vis-NIR “in-situ” spectroelectrochemistry. Experimental results are compared to standard potentials calculated at the B3LYP/cc-pVTZ level of the theory and to electronic transition energy and oscillator strength data reckoned by time dependent B3LYP/6 calculations. The consistency observed between experimental and theoretical results indicates the existence, as stable species, of the hypothesized high-spin/high-charge p- and n-doped electronic states.

2008 - Aggregation Properties of Aminoalkylsulfanyl Polythiophenes [Abstract in Atti di Convegno]
Cagnoli, Rita; Libertini, Emanuela; Mucci, Adele; Parenti, Francesca; Pinetti, Diego; Preti, Lisa; Schenetti, Luisa
abstract

The aggregation properties of an aminoalkylsulfanyl polythiophenes cayying a tromethylammonium group were characterized through a combined AFM, DOSY NMR and DLS study.

2008 - "Aminoalkylsulfanyl substituted polithiophene: an aggregation study" [Abstract in Atti di Convegno]
Parenti, Francesca; Cagnoli, Rita; Caselli, Monica; Libertini, Emanuela; Mucci, Adele; Pinetti, Diego; Ponterini, Glauco; L., Preti; Schenetti, Luisa
abstract

The aggregation properties of poly{trimethyl-[7-(3-thienylsulfanyl)heptyl]ammonium iodide-co-thiophene} (PTN+Me3) (Fig.1) were investigated through NMR, AFM, light scattering and fluorescence spectroscopy.

2008 - Aminoalkylsulfanyl Substituted Polythiophene: an Aggregation Study [Relazione in Atti di Convegno]
Parenti, Francesca; Pinetti, Diego; Ponterini, Glauco; Preti, Lisa; Schenetti, Luisa; Cagnoli, Rita; Caselli, Monica; Libertini, Emanuela; Mucci, Adele
abstract

The aggregation behaviour of poly{trimethyl-[7-(3-thienylsulfanyl)heptyl]ammonium iodide-co-thiophene} (PTN+Me3) was investigated through NMR, atomic force microscopy (AFM), dynamic light scattering (DLS), UV-Vis and fluorescence spectroscopy. The interaction with sodium ursodesoxycholate (NaUDC) causes a marked enhancement of fluorescence emission.

2008 - Amminoalchilsulfanil Politiofeni: come modulare la solubilità variando la sostituzione amminica [Abstract in Atti di Convegno]
Preti, Lisa; Cagnoli, Rita; Mucci, Adele; Parenti, Francesca; Schenetti, Luisa
abstract

E' presentata la sintesi di politiofeni recanti, sulle catene alchilsulfaniliche laterali, com sostituenti gruppi NH2, NR2, NR3+ e NRBoc. La solubilità di questi polimeri è modulata dal sostituente.

2008 - Effect of alkylsulphanyl substituent on the performance of polythiophene as donor material for bulk heterojunction solar cells [Abstract in Atti di Convegno]
P., Morvillo; E., Bobeico; Mucci, Adele; Parenti, Francesca; Schenetti, Luisa
abstract

Polymer solar cells have evolved as a promising cost-effective alternative to siliconbasedsolar cells. However, low efficiency of these plastic solar cells limits their feasibility forcommercial use. The efficiencies of polymer photovoltaic cells got a major boost with theintroduction of the bulk heterojunction (BHJ) concept consisting of an interpenetrating network ofelectron donor and acceptor materials. In this work we describe the preparation of BHJ organic solarcells using blend films of poly[4,4’-bis(alkylsulfanyl)-2,2’-bithiophene] (PST) and 1-(3-methoxycarbonyl)-propyl-1-phenyl-(6,6)C61 (PCBM). Photovoltaic cells were prepared with a layersandwiched between electrodes with different work functions. We made a comparative study of theelectrical behaviour of different devices to investigate the influence of different fabricationconditions (donor/acceptor ratio, solvent, layer thickness, device annealing, etc.). The electricalperformance of the devices were compared with the corresponding one prepared using a blend ofcommercial poly(3-hexylthiophene) (P3HT) and PCBM. The quantum efficiency of the devicefabricated with PST/PCBM blend shows a better response in the visible region compared to the onewith P3HT/PCBM. Theoretical calculations on PST and P3HT were also carried out to explain theeffect of the alkylsulphanyl substituent (compared to hexyl one) on the geometry, band gap andHOMO/LUMO levels of polythiophene.

2008 - Influence of substituents on the behaviour of polythiophene as donor in polymer-fullerene solar cells [Relazione in Atti di Convegno]
H. C., Neitzert; Mucci, Adele; Parenti, Francesca; Schenetti, Luisa; A., De Sio; A., Romano; E., Bobeico; P., Morvillo
abstract

Polymer solar cells have evolved as a promising cost-effective alternative to silicon-based solar cells.However, low efficiency of these plastic solar cells limits their feasibility for commercial use. The efficiencies ofpolymer photovoltaic cells got a major boost with the introduction of the bulk heterojunction (BHJ) conceptconsisting of an interpenetrating network of electron donor and acceptor materials.In this work we describe the preparation of BHJ organic solar cells using blend films of poly[4,4’-bis(alkylsulfanyl)-2,2’-bithiophene] (P3ST) and 1-(3-methoxycarbonyl)-propyl-1-phenyl-(6,6)C61 (PCBM). Photovoltaic cells wereprepared with a layer sandwiched between electrodes with different work functions. The electrical performance ofthe devices were compared with the corresponding one prepared using a blend of commercial poly(3-hexylthiophene)(P3HT) and PCBM. The quantum efficiency of the device fabricated with P3ST/PCBM blend shows a betterresponse in the visible region compared to the one with P3HT/PCBM.

2008 - New Aminoalkylsulfanyl Polythiophenes: Organic and Water Soluble Polymers [Abstract in Atti di Convegno]
Preti, Lisa; Cagnoli, Rita; Mucci, Adele; Parenti, Francesca; Schenetti, Luisa
abstract

The synthesis and characterization of organic and water soluble aminoalkylsulfanyl polythiophenes are reported.

2008 - Organic- and Water-Soluble Aminoalkylsulfanyl Polythiophenes [Articolo su rivista]
Cagnoli, Rita; M., Lanzi; Libertini, Emanuela; Mucci, Adele; L., Paganin; Parenti, Francesca; Preti, Lisa; Schenetti, Luisa
abstract

Six new aminoalkylsulfanyl polythiophenes (PTs), namely PTNHBoc, PTNMeBoc, PTNH2,PTNHMe, PTNMe2, and PTN+Me3, were synthesized. Four of them were obtained through Stille coupling, whereasPTNH2 and PTNHMe were obtained through deprotection via N-Boc precursors. The solubility changes goingfrom the protected amines to the quaternary ammonium salt. All the polymers are soluble in DMSO and DMF.PTNHBoc and PTNMeBoc are also soluble in CHCl3, CH2Cl2, THF, and DMPU; PTNH2 and PTNHMe aresoluble in CH3OH, whereas PTNMe2 and PTN+Me3 are soluble both in CH3OH and in H2O. These PTs show atendency toward microaggregation in solution that does not represent an obstacle to their solubility. NMR, UV-vis,and XRD results prove that they are able to reach very high conjugation lengths and ordered conformations, notonly in the solid state but also in solutions of good solvents.

2008 - Sintesi e Caratterizzazione di Octatiofeni Funzionalizzati con Gruppi Ionici o Ionizzabili [Abstract in Atti di Convegno]
Preti, Lisa; Parenti, Francesca; Mucci, Adele; Schenetti, Luisa
abstract

Sono riportate la sintesi, tramite accoppiamento ossidativo, e la caratterizzazione di octatiofeni recanti in beta catene alchilsulfaniliche funzionalizzate con gruppi COOH e NH2.

2008 - Strategies to Reduce Inter-chain Aggregation and Fluorescence Quenching in Alternated Multilayers of a Polythiophene [Articolo su rivista]
Lodi, Andrea; Caselli, Monica; Zanfrognini, Barbara; Cagnoli, Rita; Mucci, Adele; Parenti, Francesca; Schenetti, Luisa; Ponterini, Glauco
abstract

Electrostatically self-assembled multilayers of a fluorescent carboxyalkylsulfanyl polythiophene and poly(diallyldimethylammonium) were prepared using the layer-by-layer deposition approach and were structurally characterized by linear dichroism and atomic-force microscopy. Steady-state measurements revealed that fluorescence was quenched relative to the solution behaviour. The emission quantum yield was found to increase upon decreasing the polymer concentration in the dipping solution as well as by codepositing polythiophene with another polyanion, poly(sodium-4-styrenesulfonate). Fluorescence quenching was therefore attributed to the formation of non-emitting inter-chain aggregate exciton traps.Intercalation of polythiophene layers with non-emitting polymers having larger energy gaps did not result in enhanced fluorescence, thus suggesting negligible polythiophene aggregation and exciton migration across different layers. At best, we could obtain quantum yields around 0.1–0.15, about half the solution value but almost two orders of magnitude larger than found with cast or spin-cast films.

2008 - Synthesis and Characterization of ionic or ionisable octithiophenenes [Abstract in Atti di Convegno]
Preti, Lisa; Parenti, Francesca; Mucci, Adele; Schenetti, Luisa
abstract

Oligothiophenes (OTs) are materials with a precisely defined chain and conjugation length and they are usually more soluble than polymers and stable in various redox states. OTs are important molecules for applications in electronic devices, such as Field Effect Transistors (FETs), Organic Light-Emitting Diodes (OLEDs), photovoltaic cells, and sensors.2 Derivatisation of PTs with ionic or ionisable groups in the side chains provides internal charge compensation (or self-doping) generated during redox processes,3 as well as imparts water solubility. Thanks to these hydrophilic properties, ionic OTs could be able to interact with different ionic and biological molecules. This characteristic makes them interesting for applications as chemo- and bio-sensors. These applications require water-compatible materials, in the form of conjugated (and sometimes luminescent) polyelectrolytes, able to detect biomolecules through their impact on the conditions, for photoinduced charge or excitation transfer.4

2007 - Amminoalchilsulfanil politiofeni: come modulare la solubilità variando la sostituzione amminica [Abstract in Atti di Convegno]
Cagnoli, Rita; Mucci, Adele; Parenti, Francesca; Schenetti, Luisa
abstract

Nuovi politiofeni ammino funzionalizzati sono stati sintetizzati tramite accoppiamento di Stille di opportuni monomeri.

2007 - An Ab-initio theoretical study of the electrochemical grafting process of alkynil(aryl)iodonium salts on glassy carbon surfaces [Relazione in Atti di Convegno]
K., Daasbjerg; DEL PENNINO, Umberto; DE RENZI, Valentina; Fontanesi, Claudio; Parenti, Francesca; Rastelli, Augusto
abstract

The behaviour of alkynil(aryl)iodonium salts upon electrochemical reduction, on glassy carbon electrodes, is here studied by comparing both theoretical and experimental results. In particular, experimental results are obtained by means of cyclic voltammetry and chronocoulometric measurements as well as by collecting XPS spectra, while the standard electrode potential and different dissociation paths (I-C, arylic, compared to the I-C, alkynil, bond cleavage) have been characterized theoretically at the B3LYP/3-21g** level of the theory (the solvation free Gibbs energy of the cation and of the neutral radical species have been calculated by using the CPCM method).

2007 - Bulk heteojunction solar cells using a novel polybithiophene polymer [Abstract in Atti di Convegno]
P., Morvillo; E., Bobeico; C., Privato; Mucci, Adele; Parenti, Francesca; Schenetti, Luisa
abstract

In this work we describe the preparation of BHJ organic solar cells using blend films of poly[4,4’-bis(alkylsulfanyl)-2,2’-bithiophene] (PST) and 1-(3- methoxycarbonyl)-propyl-1-phenyl-(6,6)C61 (PCBM). Photovoltaic cells were prepared with a layer sandwiched between electrodes with different work functions. We made a comparative study of the electrical behaviour of different devices to investigate the influence of different fabrication conditions (donor/acceptor ratio, solvent, layer thickness, device annealing, etc.).

2007 - “Functionalized single–molecule magnets for molecular electronics” [Abstract in Atti di Convegno]
Cornia, Andrea; Anne Laure, Barra; Federica, Bianchi; Andrea, Caneschi; Danieli, Chiara; Dante, Gatteschi; Lapo, Gorini; Gregoli, Luisa; Monica, Maffini; Parenti, Francesca; Roberta, Sessoli; Lorenzo, Sorace; Anna Maria, Talarico
abstract

v. allegato

2007 - New Processable Aminoalkylsulfanyl Polythiophenes [Abstract in Atti di Convegno]
Cagnoli, Rita; Parenti, Francesca; Preti, Lisa; Mucci, Adele; Schenetti, Luisa
abstract

The synthesis and polymerization of novel alkylsulfanyl substituted thiophenes bearing amino end-groups is reported. The new materials were characterized by NMR, FT-IR, UV-Vis, XRPD and GPC.

2007 - New Single-Molecule Magnets by Site-Specific Substitution: Incorporation of “Alligator Clips” into Fe4 Complexes [Articolo su rivista]
A. L., Barra; F., Bianchi; A., Caneschi; Cornia, Andrea; D., Gatteschi; L., Gorini; Gregoli, Luisa; M., Maffini; Parenti, Francesca; R., Sessoli; L., Sorace; Talarico, Anna Maria
abstract

“Alligator clips” suitable for grafting on H-terminated siliconor gold surfaces have been incorporated into single-moleculemagnets (SMMs) of the Fe4 family. Tripodal ligands 2,2-bis-(hydroxymethyl)-10-undecen-1-ol (H3L1) and 11-(acetylthio)-2,2-bis(hydroxymethyl)undecan-1-ol (H3L2) have been usedto replace the six methoxide bridges in [Fe4(OMe)6(dpm)6],affording new Fe4 derivatives [Fe4(L1)2(dpm)6] (1) and[Fe4(L2)2(dpm)6] (2) in high yield (Hdpm = dipivaloylmethane).The molecular structures have been unambiguously established by XRD combined with ESI-MS and magnetic characterization techniques, including DC and AC magnetometry and high-frequency EPR spectroscopy. The twoSMMs have an S = 5 ground state and an easy-axis magneticanisotropy leading to slow relaxation of the magnetization atlow temperature, with effective anisotropy barriers of15.9(2) K in 1 and 15.1(2) K in 2.

2006 - A poly(alkylsulfanyl)thiophene functionalized with carboxylic groups [Articolo su rivista]
Cagnoli, Rita; Mucci, Adele; Parenti, Francesca; Schenetti, Luisa; Borsari, Marco; Lodi, Andrea; Ponterini, Glauco
abstract

Different routes, based on the Stille coupling, to the obtainment of a polythiophene bearing a carboxyhexylsulfanyl chain every two thiophene rings (PTCOOH) are here reported and discussed. Two PTCOOHs with different chain lengths were obtained: the shorter by hydrolysis of a polymeric ester precursor and the longer by direct Stille coupling from suitable monomers. They possess similar electrochemical properties but behave differently when aggregation and fluorescence are concerned. The PTCOOH obtained by hydrolysis is found to be fluorescent in a good solvent such as THF, and its fluorescence quantum yield decreases as the extent of aggregation increases. The polymer obtained by direct Stille coupling is less fluorescent, consistently with its proneness to aggregate. The PTCOOH obtained by hydrolysis is therefore more promising in view of the build-up of solid-state devices with exploitable fluorescence properties.

2006 - Ex vivo HR-MAS MRS of human meningiomas: A comparison with in vivo H-1 MR spectra [Articolo su rivista]
V., Tugnoli; Schenetti, Luisa; Mucci, Adele; Parenti, Francesca; Cagnoli, Rita; V., Righi; A., Trinchero; L., Nocetti; C., Toraci; L., Mavilla; Trentini, Giampaolo; E., Zunarelli; M. R., Tosi
abstract

We report on the magnetic resonance spectroscopy (MRS) characterisation of different human meningiomas. Three histological subtypes of meningiomas (meningothelial, fibrous and oncocytic) were analysed both through in vivo and ex vivo MRS experiments. The ex vivo high-resolution magic angle spinning (HR-MAS) investigations, permitting an accurate description of the metabolic profile, are very helpful for the assignment of the resonances in vivo of human meningiomas and for the validation of the quantification procedure of in vivo MR spectra. By using one- and two-dimensional experiments, we were able to identify several metabolites in different histological subtypes of meningiomas. Our spectroscopic data confirmed the presence of the typical metabolites of these benign neoplasms and, at the same time, that meningomas with different morphological characteristics have different metabolic profiles, particularly regarding macromolecules and lipids. The ex vivo spectra allowed a better understanding and interpretation of the in vivo MR spectra, showing that the HR-MAS MRS technique could be a complementary method to strongly support the in vivo MR spectroscopy and increase its clinical potentiality.

2006 - HR-MAS NMR spectroscopy in the characterization of human tissues: Application to healthy gastric mucosa [Articolo su rivista]
Schenetti, Luisa; Mucci, Adele; Parenti, Francesca; Cagnoli, Rita; Righi, V; Tosi, Mr; Tugnoli, V.
abstract

The HR-MAS is an ideal technique for the investigation of intact tissue specimens (10-50 mg) and permits the obtainment of spectra with a resolution comparable to that observed in solution in a time that does not exceed a half of an hour for a routine analysis. The potentialities of HR-MAS NMR spectroscopy in the identification of the metabolites characterizing the healthy gastric mucosa are here presented. The direct 1D H-1 NMR spectra enables only few metabolites to be confidently assigned, and the use of selected 2D experiments strongly amplify the analytical effectiveness of the technique.

2006 - One-pot synthesis of symmetric octithiophenes from asymmetric beta-alkylsulfanyl bithiophenes [Articolo su rivista]
Mucci, Adele; Parenti, Francesca; Cagnoli, Rita; Benassi, Rois; Passalacqua, Alessio; Preti, Lisa; Schenetti, Luisa
abstract

Starting from 4-(octylsulfanyl)-2,2'-bithiophene, 4-bromo-4'-(octylsulfanyl)-2,2'-bithiophene, 4-iodo-4'-(octylsulfanyl)-2,2'-bithiophene, 4-bromo-4'-[(S)-2-methylbutylsulfanyl]-2,2'-bithiophene, and 4-iodo-4'-[(S)-2-methylbutylsulfanyl]-2,2'-bithiophene, a new series of symmetrically beta-substituted octithiophenes were synthesized by one-pot oxidative coupling with FeCl3. The octithiophenes obtained are soluble in common organic solvents and show different solvatochromic properties depending on the substitution type. In particular, the bromine atom exerts a positive influence on the supramolecular organization: the brominated octithiophenes display high filmability, solvatochromism, and CD induced by aggregation (when the chiral 2-methylbutylsulfanyl group is present), properties usually observed for polythiophenes. Density functional theory (DFT) calculations were carried out an a model bithiophene (4-substituted with a methylsulfanyl group) in order to understand the possible mechanism of the growth, the regiochemistry, and the reason for the polymerization leads to an octithiophene.

2006 - Symmetric Octithiophenes: One-Pot Synthesis and ElectrochemicalProperties [Abstract in Atti di Convegno]
Preti, Lisa; Mucci, Adele; Schenetti, Luisa; Parenti, Francesca; Cagnoli, Rita; Passalacqua, Alessio; Benassi, Rois; Fontanesi, Claudio; Ferrarini, Paolo; F., Paolucci; M., Marcaccio; C., Bruno
abstract

sono stati riportati le sintesi di octatiofeni simmentrici ottenuti per accoppiamento ossidativo con FeCl3 e la loro caratterizzazione spettroscopica ed elettrochimica

2006 - Synthesis of asymmetric beta-alkylsulfanyl bithiophenes as precursors for symmetric octithiophenes [Abstract in Atti di Convegno]
Schenetti, Luisa; Mucci, Adele; Parenti, Francesca; Cagnoli, Rita; Preti, Lisa
abstract

The synthesis of 4-alkylsulfanyl bithiophenes, based on Stille coupling reaction, is reported.

2006 - Tuning Anisotropy Barriers in a Family of Tetrairon(III) Single-molecule Magnets with an S=5 Ground State [Articolo su rivista]
S., ACCORSI; A. L., BARRA; A., CANESCHI; G., CHASTANET; CORNIA, Andrea; FABRETTI COSTANTINO, Antonio; D., GATTESCHI; MORTALO', Cecilia; E., OLIVIERI; PARENTI, Francesca; P., ROSA; R., SESSOLI; L., SORACE; W., WERNSDORFER; ZOBBI, Laura
abstract

Tetrairon(III) Single-Mol. Magnets (SMMs) with a propeller-like structure exhibit tuneable magnetic anisotropy barriers in both height and shape. The clusters [Fe4(L1)2(dpm)6] (1), [Fe4(L2)2(dpm)6] (2), [Fe4(L3)2(dpm)6]·Et2O (3·Et2O), and [Fe4(OEt)3(L4)(dpm)6] (4) were prepd. by reaction of [Fe4(OMe)6(dpm)6] (5) with tripodal ligands R-C(CH2OH)3 (H3L1, R = Me; H3L2, R = CH2Br; H3L3, R = Ph; H3L4, R = tBu; Hdpm = dipivaloylmethane). The iron(III) ions exhibit a centered-triangular topol. and are linked by six alkoxo bridges, which propagate antiferromagnetic interactions resulting in an S = 5 ground spin state. Single crystals of 4 reproducibly contain at least two geometric isomers. From high-frequency EPR studies, the axial zero-field splitting parameter (D) is invariably neg., as found in 5 (D = -0.21 cm-1) and amts. to -0.445 cm-1 in 1, -0.432 cm-1 in 2, -0.42 cm-1 in 3·Et2O, and -0.27 cm-1 in 4 (dominant isomer). The anisotropy barrier Ueff detd. by a.c. magnetic susceptibility measurements is Ueff/kB = 17.0 K in 1, 16.6 K in 2, 15.6 K in 3·Et2O, 5.95 K in 4, and 3.5 K in 5. Both |D| and Ueff increase with increasing helical pitch of the Fe(O2Fe)3 core. The 4th-order longitudinal anisotropy parameter B40, which affects the shape of the anisotropy barrier, concomitantly changes from pos. in 1 (compressed parabola) to neg. in 5 (stretched parabola). With the aid of spin Hamiltonian calcns. the obsd. trends were attributed to fine modulation of single-ion anisotropies induced by a change of helical pitch.

2005 - A Theoretical Investigation on the Oligomerization of 4-Alkylsulfanyl bithiophene [Abstract in Atti di Convegno]
Passalacqua, Alessio; Parenti, Francesca; Cagnoli, Rita; Mucci, Adele; Schenetti, Luisa; Benassi, Rois
abstract

Desnity functional B3PW91 with Midix basis set was performed in order to investigate various mechanisms of growth of a symmetric octithiophene.

2005 - Palladium(II) derivatives of alkylsulfanyl substituted thiophenes as precursors of inorganic polymers: Spectroscopic, electrochemical investigations and X-ray crystal structure of trans-PdCl2[3-(butylsulfanyl)thiophene](2) [Articolo su rivista]
Antolini, Luciano; G., Minghetti; Mucci, Adele; Parenti, Francesca; Pigani, Laura; G., Sanna; Seeber, Renato; Zanardi, Chiara
abstract

Palladium(II) complexes with two thiophene derivatives bearing alkylsulfanyl chains, i.e., 3-(n-butylsulfanyl)thiophene and 4,4´-bis(n-butylsulfanyl)-2,2´-bithiophene, are synthesised and spectroscopically and electrochemically characterised. The molecular structure of PdCl2[3-(n-butylsulfanyl)thiophene]2 was determined by X-ray analysis. The properties of the complexes have been compared with those of PdCl2[3,3´-bis(n-butylsulfanyl)-2,2´-bithiophene] and of a conductive polymer partially coordinated with Pd(II), previously synthesised by us. We found that Pd(11) ions can coordinate sulfanyl sulfur atoms both in cis and trans configuration, leading to a reticulate material, where some kind of interchain bridging may be reasonably supposed to enhance the bulk conductivity.

2005 - Polymerization of Cysteine Functionalized Thiophenes [Articolo su rivista]
Cagnoli, Rita; M., Lanzi; Mucci, Adele; Parenti, Francesca; Schenetti, Luisa
abstract

Different synthetic pathways leading to polythiophenes (PTs) containing units derived from methyl N-(tert-butoxycarbonyl)-S-3-thienyl-L-cysteinate (1) and methyl N-(tert-butoxycarbonyl)-S-(2-thien-3-ylethyl)-L-cysteinate (2) were investigated. The oxidative coupling with FeCl3 applied to N-deprotected monomer 1 generates a chemically fleeting PT, whereas when applied to N-deprotected monomer 2 generates a mixture of oligomers. Two co-polymers bearing cysteine moieties, poly{[methyl N-(tert-butoxycarbonyl)-S-3-thienyl-L-cysteinate]-cothiophene}(co-PT1) and poly{[methyl N-(tert-butoxycarbonyl)-S-(2-thien-3-ylethyl)-L-cysteinate]-co-thiophene} (co-PT2), were eventuallysynthesized through Stille coupling of 2,5-bis(trimethylstannyl)thiophene and 2,5-dibromo derivative of compound 1 and through the post-functionalization with protected cysteine of a tosylate co-polymer, poly{[2-(3-thienyl)ethyl 4-methylbenzenesulfonate]-co-thiophene}(co-PTTs). UV–vis, CD, NMR and GPC analyses evidenced that these polymers are able to form chiral self-assembling structures, due to the formation of a hydrogen bond network and to p-stacks, not only in the solid state but also in solution.

2005 - Synthesis of two novel cysteine-functionalized thiophenes [Articolo su rivista]
Cagnoli, Rita; M., Lanzi; Mucci, Adele; Parenti, Francesca; Schenetti, Luisa
abstract

The synthetic approach to methyl N-(tert-butoxycarbonyl) -S- (3-thienyl)-L-cysteinate (1) and methyl N-(tert-butoxycarbonyl)-S-[2-(3-thienyl)ethyl]-L-eysteinate (2) through tosylate intermediates is reported and discussed. These compounds, which combine the properties of the cysteine side-chain with those of the thiophene ring represent both potential bioactive molecules and interesting synthons for the development of new materials.

2004 - Beta-alkylsulfanyl polythiophenes functionalized with carboxylic group [Abstract in Atti di Convegno]
Cagnoli, Rita; Mucci, Adele; Parenti, Francesca; Schenetti, Luisa
abstract

v. allegato

2004 - "Beta-functionalised polythiophenes via Stille and Suzuky coupling" [Abstract in Atti di Convegno]
Cagnoli, Rita; Parenti, Francesca
abstract

v.allegato

2004 - La Risonanza Magnetica Nucleare all'Angolo Magico (HR-MAS) applicata su campioni di origine animale e vegetale [Articolo su rivista]
V., Righi; Parenti, Francesca; V., Tugnoli; Schenetti, Luisa; Mucci, Adele; Cagnoli, Rita; Mr, Tosi
abstract

Nuclear Magnetic Resonance (NMR) spectroscopy, widely employed for the identification and structural characterization of organic compounds, nowdays allows intact semisolid and solid samples, like animal and vegetable tissues, to be anlyzed thanks to the introduction of High Resolution Magic Angle Spinning (HR-MAS) probes. The results of a 1-H NMR HR-MAS study on cauliflower (Brassica oleracea) stem and on a chicker liver are reported.

2004 - Poly[3-hexyl-4-(6-bromohexyl)thiophene]: A key-intermediate for the synthesis of self-plastifying multifunctional polythiophenes [Articolo su rivista]
P., COSTA BIZZARRI; M., Lanzi; L., Paganin; D., Caretti; Parenti, Francesca
abstract

The synthesis and chemical polymerization of a thiophene disubstituted with an alkylic and an u-bromine functionalized oligomethylenicchain is described. The obtained polymer, namely the poly[3-hexyl-4-(6-bromohexyl)thiophene], is completely soluble in common organicsolvents and its structural, thermal and chemical–physical properties are compared with those of a ‘conventional’ bromohexyl 3-substitutedpolythiophene. The new polymer may be considered as a key-intermediate for the synthesis of multifunctional soluble polythiophenes sinceits self-plastifying feature may permit the insertion on the polymeric side-chains, by simple post-polymerization functionalization reactions,of sterically demanding or strongly interacting functional groups, without final solubility being compromised.q 2004 Elsevier Ltd. All rights reserved.

2004 - Synthesis and Characterisation of New Polythiophenes Functionalised with Ionic Groups [Abstract in Atti di Convegno]
Cagnoli, Rita; Mucci, Adele; Parenti, Francesca; Schenetti, Luisa
abstract

The synthesis and characterisation of new polythiophenes functionalised with ionic or ionisable groups is reported

2003 - A self-assembling polythiophene functionalised with a cysteine moiety [Articolo su rivista]
Mucci, Adele; Parenti, Francesca; Schenetti, Luisa
abstract

A new copolymer bearing a cysteine moiety, designed for molecular interaction, metal-ion-detection, and chiral recognition, was synthesized starting from the diborom derivative of methyl N-(tert-butoxycarbonyl)-S-thien-3-ylcysteinate and distannylthiophene through a Stille coupling reaction. UV-vis spectroscopy, circular dichroism, NMR spectroscopy, and gel permeation chromatography analyses evidenced that this polymer is able to form self-assembling structures, through the formation of a hydrogen-bond network, not only in the solid state but also in solution.

2003 - Copolimeri a base tiofenica: Sintesi e copolimerizzazione del 7-(3-tienilsulfanil)eptanonitrile [Abstract in Atti di Convegno]
Cagnoli, Rita; Mucci, Adele; Parenti, Francesca; Schenetti, Luisa
abstract

Sono riportate la sintesi e copolimerizzazione del 7-(3-tienilsulfanil)eptanonitrile per l'ottenimento di copolimeri a base tiofenica

2003 - Differential pulse techniques on modified conventional-size and microelectrodes. Electroactivity of poly[4,4'-bis(butylsulfanyl)-2,2'-bithiophene] coating towards dopamine and ascorbic acid oxidation. [Articolo su rivista]
S., Lupu; Parenti, Francesca; Pigani, Laura; Seeber, Renato; Zanardi, Chiara
abstract

Poly[4,4'-bis(butylsulfanyl)-2,2'-bithiophene] modified conventional-size and (ultra)microelectrodes are first investigated in acetonitrile and quasi-neutral aqueous solution with respect to the repeatability of the responses obtained both in cyclic voltammetry and in differential pulse voltammetry. The reactivity towards ferrocene and hydroquinone, chosen as benchmark oxidizable substances in the two media, respectively, is considered. Comparison is made with the behavior of poly(3-methylthiophene) as electrode coating, which is one of the most commonly used redox mediators in amperometric sensors based on coatings consisting of conducting polymers. The results confirm the appealing properties of poly[4,4'-bis(butylsulfanyl)-2,2'-bithiophene], previously evidenced by us in different electrochemical studies: it exhibits particularly high stability and the characteristics of the current/potential curves obtained make it particularly suitable for analytical purposes. After performing these tests, the quantitative determination of dopamine by modified microelectrode is examined and the simultaneous voltammetric determination of ascorbic acid and dopamine is considered. The possibility of working profitably with a microelectrode at very low buffer-supporting electrolyte concentration is ascertained.

2003 - Radical ions from 3,3 ''',3 ''''-tris(butylsulfanyl)-2,2 ': 5 ',2 '': 5 '',2 ''',5 ''',2 '''': 5 '''',2 '''''-sexithiophene: An experimental and theoretical study of the p- and n-doped oligomer [Articolo su rivista]
A., Alberti; B., Ballarin; M., Guerra; D., Macciantelli; Mucci, Adele; Parenti, Francesca; Schenetti, Luisa; Seeber, Renato; Zanardi, Chiara
abstract

The 3,3',3' tris(butylsulfanyl)-2,2':5,2:5,2',5',2:5, 2'- sexithiophene 1 was investigated through spectroscopic (NMR, EPR, UV/Vis-NIR), electrochemical, spectroelectrochemical and theoretical (DFT) studies. The charged species obtained upon its oxidation and reduction were characterised, showing that 1 can exist in at least five different oxidation states, that is, a neutral species, a radical cation, a dication, a radical anion, and a dianion. The long term stability of the radical cation 1(+circle) was evidenced by the H-1 NMR study in the presence of small quantities of trifluoroacetic acid (TFA). This approach allowed a comparison of the relative broadening of proton signals of 1, induced by the electron exchange process with traces of radical cation 1(+circle), and the hfc (hyperfine coupling) constants obtained from the EPR study and DFT calculations. In the radical cation, all of the heterocyclic sulphur atoms are not significantly involved in the delocalisation of the unpaired electron, whereas the opposite holds for the radical anion. Time-dependent DFT calculations reproduced well the wavelengths of the optical transitions observed in the spectroelectrochemical experiments for all the five oxidation states and support the formation of the dianion 1(2-).

2003 - Sintesi di Polimeri beta-sostituiti con catene alchil sulfaniliche funzionalizzate [Abstract in Atti di Convegno]
Cagnoli, Rita; Mucci, Adele; Parenti, Francesca; Schenetti, Luisa
abstract

Sono riportate alcune sintesi di politiofeni beta-sostituiti con catene alchil sulfaniliche funzionalizzate

2003 - Sintesi di Polimeri beta-sostituiti con catene alchil sulfaniliche funzionalizzate [Abstract in Atti di Convegno]
Cagnoli, Rita; Mucci, Adele; Parenti, Francesca; Schenetti, Luisa
abstract

Sono riportate alcune sintesi di Polimeri beta-sostituiti con catene alchil sulfaniliche funzionalizzate e la caratterizzazione dei materiali ottenuti

2003 - The effect of Pd(II) coordination on the properties of an alkylsulfanyl substituted polythiophene. Comparison with the corresponding monomer [Articolo su rivista]
Mucci, Adele; Parenti, Francesca; Pigani, Laura; Seeber, Renato; Zanardi, Chiara; M. I., Pilo; N., Spano; M., Manassero
abstract

The synthesis of a conducting polymer partially coordinated with Pd(II) ions is reported. The aim is to study the influence of the metal on the properties of the material as a whole, which is very appealing for possible applications in the field of amperometric sensors. An alkylsulfanyl substituted polythiophene is used in this first approach, due to the well known affinity of the sulfur atom for soft metals. The interaction between the organic and inorganic moieties results in the easy formation of partially coordinated polymer. The presence of the metal ions is found to affect the chemical, physical, and electrochemical properties of the organicmacromolecules, owing to interactions between the polymer p-conjugation system and the metal d orbitals.Synthesis and characterisation of the relevant monomer complex helps to better understand the behaviour of the complex polymer-metal system.

2002 - A new polymer-like octathiophene. Synthesis and properties of 4,3'',4''''',4'''''''-tetrabromo-4',4''',3'''',3''''''-tetra(octylsulfanyl)-2,2':5',2'':5'',2''':5''', 2'''':5'''',2''''':5''''', 2'''''':5'''''',2''''''' -octathiophene [Abstract in Atti di Convegno]
Parenti, Francesca; A., Bellei; Mucci, Adele; Schenetti, Luisa
abstract

The oxidative polymerization of 4-bromo-4'-octylsulfanyl-2,2'-bithiophene afforded a symmetric octithiophene able to form homogeneous films, that was characterized through NMR, MS, GPC.

2002 - Complessi di Pt(II) con cisteina S-funzionalizzata [Abstract in Atti di Convegno]
Parenti, Francesca; A., Bellei; Mucci, Adele; Schenetti, Luisa
abstract

Sono riportate le sintesi e le caratterizzazioni di complessi di Pt(II) con cisteina S-funzionalizzata

2002 - Erratum: On the Recovery of 3JH,H and the Reduction of Molecular Symmetry by Simple NMR Inverse Detection Experiments [Articolo su rivista]
Mucci, Adele; Parenti, Francesca; Schenetti, Luisa
abstract

Simple 1H,13C correlation spectra obtained by inverse detection techniques provide useful evidence of molecular symmetry. The emblematic case of cis- and trans-stilbenes together with that of a symmetric terthiophene are reported as examples. The effects of a reduction of symmetry on both direct and long-range correlations are reported

2002 - On the recovery of (3)J(H,H) and the reduction of molecular symmetry by simple NMR inverse detection experiments [Articolo su rivista]
Mucci, Adele; Parenti, Francesca; Schenetti, Luisa
abstract

Simple H-1, C-13 correlation spectra obtained by inverse detection techniques provide useful evidence of molecular symmetry, The emblematic case of cis- and trans-stilbenes together with that of a symnietric terthiophene are reported as examples. The effects of a reduction of symmetry on both direct and long-range correlations are reported.

2002 - Polimeri conduttori coordinati con ioni metallici come nuovi materiali per sensori elettrocatalitici [Abstract in Atti di Convegno]
Mucci, Adele; Parenti, Francesca; Pigani, Laura; M. I., Pilo; P., Piu; G., Sanna; Schenetti, Luisa; Seeber, Renato; N., Spano; Zanardi, Chiara
abstract

v. allegato

2002 - Sintesi e proprietà di octatiofeni beta-funzionalizzati [Abstract in Atti di Convegno]
A., Bellei; Mucci, Adele; Parenti, Francesca; Schenetti, Luisa
abstract

E' riportato uno studio sulla filmabilità di octitiofeni funzionalizzati con gruppi alchilsulfanilici. Sono stati confrontati diversi sistemi di depisizione (casting, spin coating, Langmuir-Blodgett).

2001 - Beta-Functionalised alpha,alpha'-conjugated oligothiophenes with alkylsulfanyl groups: synthesis and characterisation [Articolo su rivista]
Mucci, Adele; Parenti, Francesca; Schenetti, Luisa; Zanardi, Chiara
abstract

alpha-oligothiophenes are important materials for optical and electronic devices and are used as model compounds for the characterization of charge carriers in conjugated chains. The presence of beta-alkylsulfanyl groups on the thiophene ring reduces the band-gap between ground and excited state, and influence the electrical and optical properties in a positive manner in relation to possible applications of these materials. the syntheses of a homologous series of alkylsulfanyl oligothiophenes, up to octithiophenes, is discussed

2001 - Bromo- e dibromo-bitiofeni come precursori di bitiofeni beta-funzionalizzati [Abstract in Atti di Convegno]
Mucci, Adele; Parenti, Francesca; Schenetti, Luisa; Zanardi, Chiara
abstract

Sono riportate le metodologie sintetiche che permettono di partire da bromo- e dibromo-bitiofeni per ottenere bitiofeni beta-funzionalizzati.

2001 - β-Functionalised α,α’-conjugated oligothiophenes with alkylsulfanyl groups: synthesis and characterisation [Capitolo/Saggio]
Mucci, A.; Zanardi, C.; Parenti, F.; Schenetti, L.
abstract

α-Oligothiophenes are important materials for optical and electronic devices and are used as model compounds for the characterisation of charge carriers in conjugated chains. The presence of substituents in β- position of the thiophene ring improves solubility and processability and enables the chemical-physical properties of these materials to be modulate. Among the substituents, the choice of alkylsulfanyl groups is due to the electron donor effect of the sulfur atom which positively reduces the band-gap between ground and excited state, and influences the electrical and optical properties interesting in relation to possible applications of these materials. A synthesis of a homologous series of β-substituted oligothiophenes bearing alkylsulfanyl groups up to octatiophenes is discussed. The alkyl residues of the alkylsulfanyl moieties are methyl-, butyl-, octyl- and (+)-(S)-2-methylbutyl groups. The regiochemistry of all synthesised oligomers is unambiguously assessed by using 1H and 13C NMR spectroscopy. The electrochemical behaviour of some of these derivatives is analysed in relation to their potential applicability in electrochemical devices.

2001 - Metal-catalised cross coupling of beta-alkylsulfanyl thiophenes [Abstract in Atti di Convegno]
Mucci, Adele; Parenti, Francesca; Schenetti, Luisa; Zanardi, Chiara
abstract

The synthesis of three isomeric bithiophenes via different coupling reactions was reported.

2001 - Politiofeni funzionalizzati con gruppi alchilsulfanilici [Abstract in Atti di Convegno]
Mucci, Adele; Parenti, Francesca; Schenetti, Luisa; Seeber, Renato; Zanardi, Chiara
abstract

v.allegato

2001 - Synthesis and Spectroscopic and Electrochemical Characterisation of a Conducting Polythiophene Bearing a Chiral β-Substituent: Polymerisation of (+)-4,4′-Bis[(S)-2-methylbutylsulfanyl]-2,2′-bithiophene [Articolo su rivista]
Iarossi, Dario; Mucci, Adele; Parenti, Francesca; Schenetti, Luisa; Seeber, Renato; Zanardi, Chiara; Forni, Arrigo; Tonelli, Massimo
abstract

A regioregular head-to-head/tail-to-tail poly(b,b'-disubstituted bithiophene) P1 was synthesised by chemical and electrochemical polymerisation of 2,2'-bithiophene that bears (S)-2-methylbutylsulfanyl chains in the b and b'-positions. The polymer was characterised by GPC, NMR and UV/Vis spectroscopy,CD, AFM and by electrochemical and conductivity measurements.The CD spectra of P1 in solutions in which poor solvents are present show interesting features and allow the presenceof different optically active species to be distinguished. Upon varying the casting conditions of P1, different relativeamounts of grainy and homogeneous aggregated phases were observed in AFM micrographies of films and correspondingnegative or positive first Cotton effects were found in the CD spectra. AFM, CD and UV/Vis characterisations were also performed on an electrogenerated optically active polymerPE1, in order to make a comparison with the chemically synthesised one. The interesting, small band gap of P1 allowsfor easy p- and n-electrochemical doping.

2001 - 4,3'',4''''',4'''''''-Tetrabromo-4',4''',3'''',3''''''-tetra(ottilsulfanil)-2,2':5',2'':5'',2''':5''',2'''':5'''',2''''':5''''',2'''''':5'''''',2'''''''-octatiofene: Sintesi e proprieta' [Abstract in Atti di Convegno]
Mucci, Adele; Parenti, Francesca; Schenetti, Luisa; Zanardi, Chiara
abstract

E' riportata la sintesi , a partire da un bitiofene asimmetricamente disostituito in 4- e 4'-, di un octatiofene simmetrico sostituito in beta con catene ottilsulfaniliche e atomi di bromo. L'octatiofene, che ha una spiccata tendenza a formare film omogenei, è stato caratterizzato tramite NMR, GPC, UV-Vis.

2000 - Politiofeni: sintesi di precursori per la reazione di polimerizzazione [Abstract in Atti di Convegno]
Parenti, Francesca
abstract

Sintesi di oligotiofeni beta funzionalizzati come sintoni per la reazione di polimerizzazione

2000 - Poli[4,4'-bis(metilbutilsulfanil)-2,2'-bitiofene]: Sintesi e Proprietà [Abstract in Atti di Convegno]
Iarossi, Dario; Mucci, Adele; Parenti, Francesca; Schenetti, Luisa; Zanardi, Chiara; Forni, Arrigo
abstract

Sono riportate la sintesi e la caratterizzazione del poli[4,4'-bis(metilbutilsulfanil)-2,2'-bitiofene.