Synthesis of an Optically Active Poly(phenylacetylene) Bearing Galvinoxyl Radicals for Magnetic Materials

An optically active polyradical was first synthesized by copolymerization of (4-ethynylphenyl)hydrogalvinoxyl and chiral acetylene monomer using Rh-catalyst. The circular dichroism spectrum of the polyradical showed a Cotton effect indicating the exess of one-handed helix backbone and the induced chirality of side-chain galvinoxyl units. Intermoleculer antiferromagnetic interaction observed for the polyradical was larger than that of the corresponding polyradical without excess of one-handed helix.

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