Inhibitory role of carbon monoxide in palladium(II)-catalyzed nonalternating ethene/carbon monoxide copolymerizations and the synthesis of polyethene-block-poly(ethene-alt-carbon monoxide)

We report the first well-defined palladium-based system for the living homopolymerization of ethene, as well as the living copolymerization of ethene with carbon monoxide. We demonstrate this by the synthesis of polyethene-block-poly-(ethene-alt-carbon monoxide). In addition, it has been possible to monitor chain growth by sequential insertions of carbon monoxide and ethene into palladium-carbon bonds. The mechanistic studies have also allowed us to pinpoint the hitherto not well-understood reason for the general failure to obtain alkene/carbon monoxide copolymers with low carbon monoxide content.