Supramolecular Fullerene Materials:  Dendritic Liquid-Crystalline Fulleropyrrolidines

Stéphane Campidelli, Julie Lenoble, Joaquín Barberá,* Francesco Paolucci,*§ Massimo Marcaccio,§ Demis Paolucci,§ and Robert Deschenaux*
Institut de Chimie, Université de Neuchâtel, Avenue de Bellevaux 51, Case Postale 2, 2007 Neuchâtel, Switzerland, Química Orgánica, Facultad de Ciencias-Instituto de Ciencia de Materiales de Aragón, Universidad de Zaragoza-CSIC, 50009 Zaragoza, Spain, and Dipartimento di Chimica “G. Ciamician”, Università di Bologna, via Selmi 2, 40126 Bologna, Italy
Macromolecules, 2005, 38 (19), pp 7915–7925
DOI: 10.1021/ma051359g
Publication Date (Web): August 20, 2005
Copyright © 2005 American Chemical Society

 Université de Neuchâtel.

*

 Corresponding author. E-mail:  robert.deschenaux@unine.ch.

 Universidad de Zaragoza-CSIC.

§

 Università di Bologna.

Abstract

[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 fullerene dendrimer, which was found to be nonmesomorphic, all fullerene-based dendrimers gave rise to a smectic A phase. The liquid-crystalline fullerenes led to two different supramolecular organizations within the smectic layers:  for the second-generation dendrimers, the molecules are oriented in a head-to-tail fashion within the layers; for each molecule the cyanobiphenyl units point in the same direction. For the dendrimers of third and fourth generations, the dendritic core extends laterally, parallel to the layer planes; the mesogenic units are oriented above and below the dendritic core. For the aldehyde precursors, only one organization inside the layers was obtained, similar to the one observed for the third and fourth fullerene-based dendrimers. Cyclic voltametry investigations displayed several one-electron and multielectron reduction processes; no significant interaction in the ground state between the fullerene and the dendrimer was noticed. The title compounds showed the typical electrochemical stability of fulleropyrrolidines.

Article Tools

SciFinder subscribers:  Click to sign in | Not a SciFinder subscriber? Learn more at www.cas.org

History

  • Published In Issue September 20, 2005
  • Received June 25, 2005
    Revised Manuscript Received July 20, 2005

Recommend & Share