Nickel-catalyzed polymerization of a substituted sulfoxonium ylide

The homopolymerization of (dimethylamino)phenylsulfoxonium ethylide, a substituted sulfoxonium ylide, is reported. Treatment of the monomer with a readily available Ni(II) catalyst afforded poly[(1-butene)-ran-(2-butene)-ran-(ethylene)] in good yield and high molecular weight. Varying the initial monomer-to-catalyst feed ratio enabled control over the molecular weights of the polymers produced. The polymerization mechanism appears to proceed in a chain growth fashion that entails the addition of ethylide units to growing polymer chains in conjunction with the expulsion of (dimethylamino)phenyl sulfoxide as a byproduct.