Palladium-based system for the polymerization of acrylates.: Scope and mechanism

The neutral palladium complex [Pd(C6F5)Br(NCMe)(2)].(I) was found to effect the polymerization of acrylates upon addition of 1 equiv of a monodentate phosphine or pyridine or an excess of halide. Methyl methacrylate was not polymerized, and furthermore, its addition. stopped the progress of independently initiated methyl acrylate polymerization in the phosphine-based system. Addition of ethene also inhibited the polymerization of methyl acrylate. However, over 10 mol % incorporation of 1-hexene in the polymer was achieved when the latter was added together with methyl acrylate. The polymerizaion mechanism is discussed.