Transition metal carbonyl catalysts for polymerizations of substituted acetylenes

Most of the existing metal carbonyl catalysts for acetylene polymerizations need to be preactivated by chlorine-containing additives or by UV irradiat ion in halogenated solvents. In this work, we developed a series of "simple " metal carbonyl catalysts of general structure M(CO)(x)L-y (M = Mo, W), no ne of which require additives or pre-photoirradiation, most of which are ai r- and moisture-stable, and some of which work well in nonhalogenated solve nts. The acetonitrile complexes M(CO)(3)(NCCH3)(3) initiated polymerization s of a variety of mono- and disubstituted acetylenes at room temperature. T he arene and diene complexes W(CO)(3)(mes) and Mo(CO)(3)(nbd) (mes = mesity lene, nbd = 2,5-norbornadiene) are tolerant of polar groups and effected po lymerizations of functional acetylenes containing ester, ether, and cyano g roups. The halogenated complexes MI2(CO)(3)(NCCH3)(2) catalyzed polymerizat ions of phenylacetylene in toluene. The chlorine-containing acetylene monom ers ClC drop CC6H5 and ClC drop CC6H13 were readily polymerized by the Mo c omplexes in nonhalogenated solvents such as toluene and dioxane, giving pol ymers with high molecular weights (M-w up to 883 x 10(3)) in high yields (u p to 100%).