Université de Neuchâtel

Liquid-Crystalline Bisadducts of [60]Fullerene

Campidelli, Stéphane ; Vázquez, Ester ; Milic, Dragana ; Lenoble, Julie ; Atienza Castellanos, Carmen ; Sarova, Ginka ; Guldi, Dirk M. ; Deschenaux, Robert ; Prato, Maurizio

In: The Journal of Organic Chemistry (JOC), 2006, vol. 71, no. 20, p. 7603–7610

A second-generation cyanobiphenyl-based dendrimer was used as a liquid-crystalline promoter to synthesize mesomorphic bisadducts of [60]fullerene. Liquid-crystalline trans-2, trans-3, and equatorial bisadducts were obtained by condensation of the liquid-crystalline promoter, which carries a carboxylic acid function, with the corresponding bisaminofullerene derivatives. A monoadduct...

Université de Neuchâtel

Electrochemical properties of a liquid-crystalline mixed fullerene–ferrocene material and related species

Carano, Maurizio ; Chuard, Thierry ; Deschenaux, Robert ; Even, Michael ; Marcaccio, Massimo ; Paolucci, Francesco ; Prato, Maurizio ; Roffia, Sergio

In: Journal of Materials Chemistry, 2002, vol. 12, no. 4, p. 829-833

The electrochemical properties of a fullerene–ferrocene liquid crystal are reported. The electrochemical study was carried out under strictly aprotic conditions: a total of seven reduction peaks were detected in the negative potential region, and two oxidation peaks in the positive potential one. Comparison of the data with those obtained from suitable model compounds (i.e., analogous...

Université de Neuchâtel

A Mixed Fullerene-Ferrocene Thermotropic Liquid Crystal: Synthesis, Liquid-Crystalline Properties, Supramolecular Organization and Photoinduced Electron Transfer

Even, Michaël ; Heinrich, Benoît ; Guillon, Daniel ; Guldi, Dirk M. ; Prato, Maurizio ; Deschenaux, Robert

In: Chemistry - A European Journal, 2001, vol. 7, no. 12, p. 2595-2604

Grafting of a ferrocene-containing liquid-crystalline malonate derivative to C60 led to the mixed fullerene-ferrocene material 1 which gave rise to a smectic A phase. Cholesterol was used as liquid-crystalline promoter. X-ray diffraction experiments and volumetric measurements indicated that 1 is organized in double layered structures. The corresponding supramolecular...

Université de Neuchâtel

Synthesis of dendrimer-carbon nanotube conjugates

García, A. ; Herrero, M. A. ; Frein, Stéphane ; Deschenaux, Robert ; Muñoz. R. ; Bustero, I. ; Toma, F. ; Prato, Maurizio

In: Physica Status Solidi (a), 2008, vol. 205, no. 6, p. 1402-1407

We describe the coupling between Carbon Nanotubes (CNTs) and a second-generation cyanophenyl-based dendrimer. The goal of our work is the synthesis of highly functionalized CNTs without provoking damage to the conjugated π-system. One approach is the attachment of dendrimers with a high density of functional groups to the CNTs. These groups serve as anchor points for further reactions. With this...

Université de Neuchâtel

Photophysical, electrochemical, and mesomorphic properties of a liquid-crystalline [60]fullerene–peralkylated ferrocene dyad

Campidelli, Stéphane ; Séverac, Marjorie ; Scanu, David ; Deschenaux, Robert ; Vázquez, Ester ; Milic, Dragana ; Prato, Maurizio ; Carano, Maurizio ; Marcaccio, Massimo ; Paolucci, Francesco ; Rahman, G. M. Aminur ; Guldi, Dirk M.

In: Journal of Materials Chemistry, 2008, vol. 18, p. 1504-1509

Two fullerene–peralkylated ferrocene derivatives were synthesized: (1) a liquid-crystalline dyad (compound 1) was obtained by introduction of nonamethyl ferrocene into a liquid-crystalline fullerene derivative and (2) a reference compound (compound 2) was synthesized by attachment of nonamethyl ferrocene to a fulleropyrrolidine. The liquid-crystalline dyad displayed an enantiotropic smectic A...

Université de Neuchâtel

A dendritic fullerene–porphyrin dyad

Campidelli, Stéphane ; Deschenaux, Robert ; Swartz, Angela ; Rahman, G. M. Aminur ; Guldi, Dirk M. ; Milic, Dragana ; Vázquez, Ester ; Prato, Maurizio

In: Photochemical & Photobiological Sciences, 2006, vol. 5, no. 12, p. 1137-1141

We describe the synthesis, characterization and photophysical properties of a fullerene derivative whose structure includes a Zn-porphyrin and a second generation liquid-crystalline (LC) dendrimer. The size of the fullerene and porphyrin units with respect to the size of the LC dendrimer prevents the formation of liquid-crystalline phases. However, this system gives interesting photoinduced...

Université de Neuchâtel

Liquid-crystalline fullerene–ferrocene dyads

Campidelli, Stéphane ; Vázquez, Ester ; Milic, Dragana ; Prato, Maurizio ; Barberá, Joaquín ; Guldi, Dirk M. ; Marcaccio, Massimo ; Paolucci, Demis ; Paolucci, Francesco ; Deschenaux, Robert

In: Journal of Materials Chemistry, 2004, vol. 14, p. 1266 - 1272

The 1,3-dipolar cycloaddition reaction was used to assemble fullerene, ferrocene and a second-generation liquid-crystalline cyanobiphenyl-based dendrimer. The targeted compound displayed an enantiotropic smectic A phase from 40 to 135 °C. The d-layer spacing was determined by X-ray diffraction, and was found to be independent of temperature with a value of 95 Å. Molecular modeling and...