Université de Neuchâtel

Supramolecular Fullerene Materials: Dendritic Liquid-Crystalline Fulleropyrrolidines

Campidelli, Stéphane ; Lenoble, Julie ; Barberá, Joaquín ; Paolucci, Francesco ; Marcaccio, Massimo ; Paolucci, Demis ; Deschenaux, Robert

In: Macromolecules, 2005, vol. 38, no. 19, p. 7915–7925

[60]Fullerene-containing liquid-crystalline dendrimers were synthesized from the first to the fourth generation by applying the 1,3-dipolar cycloaddition reaction from a mesomorphic dendritic-type aldehyde derivative, sarcosine (N-methylglycine) or glycine and C60. The cyanobiphenyl unit was used as a liquid-crystalline promoter. With the exception of the first-generation...

Université de Neuchâtel

Highly Fluorescent Liquid-Crystalline Dendrimers Based on Borondipyrromethene Dyes

Frein, Stéphane ; Camerel, Franck ; Ziessel, Raymond ; Barberá, Joaquín ; Deschenaux, Robert

In: Chemistry of Materials, 2009, vol. 21, no. 17, p. 3950–3959

Fluorescent mesomorphic materials have been synthesized by grafting difluoro-bora-diaza-s-indacene (F-Bodipy) onto first-, second-, and third-generation liquid-crystalline poly(aryl ester) dendrons functionalized with cyanobiphenyl units. The second- and third-generation dendrimers give rise to smectic A phases; the first-generation dendrimer shows a nematic phase and an...

Université de Neuchâtel

Mesomorphic Metallo-Dendrimers Based on the Metal−Metal Bonded Ru2(CO)4 Sawhorse Unit

Frein, Stéphane ; Auzias, Mathieu ; Sondenecker, Aline ; Vieille-Petit, Ludovic ; Guintchin, Boris ; Maringa, Natacha ; Süss-Fink, Georg ; Barberá, Joaquín ; Deschenaux, Robert

In: Chemistry of Materials, 2008, vol. 20, no. 4, p. 1340-1343

Dinuclear ruthenium complexes containing the stable metal−metal bonded Ru2(CO)4 sawhorse unit with two dendritic carboxylato bridges have been synthesized and characterized. All complexes Ru2(CO)4(O2CR)2L2 (R = R1, R2, R3) containing cyanobiphenyl-based poly(arylester) dendrons of first...

Université de Neuchâtel

Red and Blue Liquid-Crystalline Borondipyrromethene Dendrimers

Mula, Soumyaditya ; Frein, Stéphane ; Russo, Virginie ; Ulrich, Gilles ; Ziessel, Raymond ; Barberá, Joaquín ; Deschenaux, Robert

In: Chemistry of Materials, 2015, vol. 27, no. 7, p. 2332-2342

We have designed a series of modular and fluorescent poly(arylester) dendrimers functionalized with cyanobiphenyl subunits and fluorescent borondipyrromethene (Bodipy) dyes. The green emitter is a Bodipy with four methyl groups, and the Bodipy dye possessing extended conjugation with two methyl and two vinyl groups acts as a red emitter. The design element of these architectures relates to a...

Université de Neuchâtel

Piling Up Pillar[5]arenes To Self-Assemble Nanotubes

Nierengarten, Iwona ; Guerra, Sebastiano ; Ben Aziza, Haifa ; Holler, Michel ; Abidi, Rym ; Barberá, Joaquín ; Deschenaux, Robert ; Nierengarten, Jean-François

In: Chemistry – A European Journal, 2016, vol. 22, no. 18, p. 6185-6189

New liquid-crystalline pillar[5]arene derivatives have been prepared by grafting first- generation Percec-type poly(benzylether) dendrons onto the macrocyclic scaffold. The molecules adopt a disc-shaped structure perfectly suited for self-organization into a columnar liquid-crystalline phase. In this way, the pillar[5]arene cores are piled up, thus forming a nanotubular wire encased within a...

Université de Neuchâtel

Macrocyclic Effects in the Mesomorphic Properties of Liquid-Crystalline Pillar[5]- and Pillar[6]arenes

Nierengarten, Iwona ; Guerra, Sebastiano ; Holler, Michel ; Karmazin-Brelot, Lydia ; Barberá, Joaquín ; Deschenaux, Robert ; Nierengarten, Jean-François

In: European Journal of Organic Chemistry, 2013, vol. 2013, no. 18, p. 3675-3684

Whereas the reaction of 1,4-bis(2-bromoethyloxy)benzene (4) with paraformaldehyde in the presence of BF3·Et2O afforded exclusively the cyclopentameric pillar[5]arene derivative (5), both cyclopenta- and cyclohexameric macrocycles 5 and 6 were obtained when the reaction of 4 with paraformaldehyde was performed at 45 °C in CHCl3 with FeCl3 as the...

Université de Neuchâtel

Liquid-Crystalline Dendrimers Designed by Click Chemistry

Guerra, Sebastiano ; Nguyen, Thi Le Anh ; Furrer, Julien ; Nierengarten, Jean-François ; Barberá, Joaquín ; Deschenaux, Robert

In: Macromolecules, 2016, vol. 49, no. 9, p. 3222-3231

Liquid-crystalline dendrimers have been prepared from second-generation Percec- type poly(benzyl ether) dendrons or second-generation poly(aryl ester) dendrons carrying cyanobiphenyl mesogens. The Janus dendrimer, which combines the two types of dendromesogens, has also been synthesized. Those compounds have been prepared under copper-catalyzed azide–alkyne cycloaddition conditions. The ...

Université de Neuchâtel

[60]Fullerene-based liquid crystals acting as acid-sensitive fluorescent probes

Pérez, Laura ; Lenoble, Julie ; Barberá, Joaquín ; de la Cruz, Pilar ; Deschenaux, Robert ; Langa, Fernando

In: Chemical Communications (ChemComm), 2008, vol. 38, p. 4590-4592

Functionalization of [60]fullerene with liquid-crystalline dendrimers and a dibutylaniline-based phenylenevinylene moiety leads to supramolecular materials, the fluorescence of which responds to acid–base stimuli.

Université de Neuchâtel

Liquid-Crystalline Thiol- and Disulfide-Based Dendrimers for the Functionalization of Gold Nanoparticles

Frein, Stéphane ; Boudon, Julien ; Vonlanthen, Mireille ; Scharf, Toral ; Barberá, Joaquín ; Süss-Fink, Georg ; Bürgi, Thomas ; Deschenaux, Robert

In: Helvetica Chimica Acta, 2008, vol. 91, no. 12, p. 2321-2337

Liquid-crystalline dendrons carrying either a thiol or disulfide function which display nematic, smectic A, columnar, or chiral nematic phases have been synthesized. Their mesomorphic properties are in agreement with the nature of the mesogenic units and structure of the dendrons. The first-generation poly(aryl ester) dendron containing two cyanobiphenyl mesogenic units was used to functionalize...

Université de Neuchâtel

Dendritic liquid-crystalline fullerene–ferrocene dyads

Campidelli, Stéphane ; Pérez, Laura ; Rodríguez-López Julián ; Barberá, Joaquín ; Langa, Fernando ; Deschenaux, Robert

In: Tetrahedron, 2006, vol. 62, no. 9, p. 2115-2122

First- and second-generation ferrocene-based dendrimers, fullerene and a second-generation liquid-crystalline poly(arylester) dendrimer carrying four cyanobiphenyl units were assembled to elaborate polyfunctional materials displaying mesomorphic and electronic properties. The targeted compounds gave rise to enantiotropic smectic A phases and organized into bilayer structures within the smectic...