Chirality induction in cyclocopolymerization XI. Bulkiness effect of 1,2-diol templates on cyclocopolymerizations of bis(4-vinylbenzoate)s with styrene

The radical cyclocopolymerizations of(R)-1-phenyl-1,2-ethanediyl, (R,R)-1,2 -diphenyl-1,2-ethanediyl, and (R,R)-1,2-di(1-naphthyl)- 1,2-ethanediyl bis( 4-vinylbenzoate)s (1d, 1e, and 1f) with styrene yielded copolymer 2 with ne w chirality in the main chain. The chirality induction was based on the con figurational arrangement. Optically active poly(methyl 4-vinylbenzoate-co-s tyrene) (3) was obtained by the removal of the chiral template in copolymer 2, followed by the treatment with diazomethane. The template having (R)- a nd (S)-configuration transmitted its chirality to the main chain in the int ramolecular cyclization of divinyl monomers to form the enantiomeric (S,S)- and (R,R)-racemo units, respectively. Repulsive steric interactions of the substituents restricted rotation around single bonds in the 1,2-diol templ ates to improve the selectivity between two raceme units.