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.