Chloro- and aryl-substituted acetylene monomers having an optically active group were polymerized by a Pd catalyst [((Bu3P)-Bu-t)PdMeCl] bearing a bulky phosphine ligand, and by MoCl5 for comparison. The corresponding disubstituted acetylene polymers with M-n's52000-19,500 and 6900-10,800 were obtained in 29-83% and 11-62% yields when the Pd and Mo catalysts were used, respectively. The formation of polyacetylenes, poly[(R)-1p], poly[(R)-1m], and poly[(S)-2p] were confirmed by SEC and the presence of a Raman scattering peak based on the alternating double bonds of the main chain. Pdbased poly[(R)-1m] exhibited CD signals around 350 nm assignable to a certain secondary structure, while Mo-based poly[(R)-1m] did not. (C) 2017 Wiley Periodicals, Inc.