A Helical Array of Pendant Fullerenes on an Optically Active Polyphenylacetylene

Abstract

A question of balls and chains: The copolymerization of an achiral fullerene and an optically active phenylacetylene yields a helical polymer (see picture) where the pendant C60 groups adopt a predominant screw‐sense along the polymer backbone. The copolymer exhibits an induced circular dichroism in the fullerene chromophoric region.

Chiral nanostructure in polymers under different deposition conditions observed using atomic force microscopy of monolayers: poly(phenylacetylene)s as a case study

“…These results indicate that the attractive force between the pendant fullerenes and the solid substrate plays a critical role in the morphology of the C 60 -based polymers and suggest that the interplay between the hydrophobic/hydrophilic nature of the support and the pendants of the polymer can be used to select the formation of a certain class of suprastructure. 49 Similar studies were carried out on low-and high-molecularweight poly(4-carboxyphenylacetylene)s (poly-3), their salts with (R)-(+)-1-(1-naphthyl)ethylamine [(R)-4, Figure 3c] and on the corresponding carboxyamides (poly-5; Figure 3c). These polymers were deposited by drop casting on mica, and AFM showed the presence of isolated chains with a helical structure.…”

“…49 More precisely, they studied a phenylacetylene copolymer [i.e., poly(1 x -co-2 1-x )], composed by two pendants: an achiral C 60 -bound and an optically active amine (i.e., (R)-[(1-phenylethyl)carbamoyl]oxy). This copolymer was deposited by drop casting both on freshly cleaved mica and on HOPG, and the morphologies of the resulting assemblies were studied by AFM (Figures 3a and 3b).…”

Atomic force microscopy observation of a helical poly(phenylacetylene) bearing aza‐18‐crown‐6 ether pendants induced by amino acids

“…DNA, 1,3 block copolymers, 6 -8 polyelectrolytes, 9 and carbon nanotubes 10,11 have often been used for such purposes. The direct observation of the helical structures of polymers 3,[15][16][17][18][19] and helical assemblies derived from small molecules 20 -22 by SPM is an attractive goal but still remains difficult and rare.…”

The transformation of chiral signals into macroscopic properties of materials using chirality-responsive polymers

“…Yashima et al 62,63 have also utilized covalent complexation to construct chiral fullerene supramolecular assemblies in which achiral fullerenes were copolymerized with chiral phenylacetylene components to form stereoregular polymers with fullerene pendants. The prepared copolymers adopted one-handed helical structures, and the fullerene groups were arranged in helical arrays with their screw sense along the polymer backbone.…”