Synthesis of a Novel [60]Fullerene Pearl-Necklace Polymer, Poly(4,4*-carbonylbisphenylene trans-2- [60]fullerenobisacetamide)

ABSTRACT: A novel [60]fullerene pearl-necklace polymer, poly(4,49-carbonylbisphe-nylene trans-2-[60]fullerenobisacetamide), was synthesized by a direct polycondensa-tion of trans-2-[60]fullerenobisacetic acid with 4,49-diaminobenzophenone in the pres-ence of large excesses of triphenyl phosphite and pyridine. In the present polymer, [60]fullerene pearls and diamine linkers were attached to each other by methano-carbonyl connectors. The molecular weight Mw of the polymer was determined to be 4.5 3 104 on the basis of the TOF-MS, and a GPC analysis of the polymer using polystyrene standards showed a weight-average molecular weight of 5.3 3 104. The UV-vis spec-trum of the resultant polymer in N,N-dimethylacetamide (DMAc) exhibited a broad absorption (lmax 310 nm, « 2.1 3 10 4 L z mol21 z cm21), tailing to longer wavelengths, and a fluorenscence peak centered at 550 nm was observed in DMAc. There was observed a large downfield-shift of the cyclopropane methyne proton in the 1H-NMR spectra from 4.57 ppm of the ethyl ester to 5.78 ppm of the polyamide. These observa-tions indicate that the present polyamide is a high-molecular-weight [60]fullerene pearl-necklace polymer and that the cyclopropane rings are efficient to make the [60]fullerene cages and the diamine components conjugatable. © 1999 John Wiley & Sons