Polymerization of phenylacetylene by cationic acetylacetonate palladium complexes

Abstract

A series of cationic acetylacetonate palladium complexes were demonstrated to be active for the polymerization and oligomerization of phenylacetylene. Catalyst screening and optimization have determined the superior activity of complex [(acac)Pd(TOMPP)2]BF4 (TOMPP – tris(2-methoxyphenyl)phosphine) for the stereospecific polymerization of phenylacetylene in non-coordinating solvents as well as in an aqueous emulsion. Catalyst turnover frequencies of 100–160 h−1 were observed (Mw = (10–27)·104 with PDI = 1.7–2.3, cis double bond content in PPA up to 95%). The effect of temperature, solvent nature, and the use of cocatalyst, BF3·OEt2, have been studied.