Enantioselective, alternating copolymerization of carbon monoxide and olefins

Enantioselective, alternating copolymerizations of carbon monoxide with sty rene, dicyclopentadiene, and methylcyclopentadiene dimer were carried out w ith a palladium catalyst modified by 1,4-3,6-dianhydro-2,5-dideoxy-2,5-bis( diphenyl phosphino)-L-iditol. Chiral diphosphine was proven to be effective at enantioselective copolymerization. In the copolymers, some of the secon d double bonds of alternating poly(1,4-ketone) were carbonylated. Optical r otation, elemental analysis, and spectra of H-1 NMR, C-13 NMR, and IR showe d that the copolymers had isotactic, alternating poly(1,4-ketone) structure s. An oxidant and an organic acid were the promoters of the copolymerizatio n. (C) 2000 John Wiley & Sons, Inc.