Nickel catalysts in the realm of Coordinative Chain Transfer Polymerization: paradox and opportunities

Coordinative Chain Transfer Polymerization, or CCTP, has gained much interest in the last years. This can notably be ascribed to its ability to allow catalyst economy, but also the design of original polyolefinic microstructures. Group 10 metals such as Ni were much less studied for CCTP comparatively to other metals. Indeed, the β-H transfer/elimination processes associated to these metals can be considered at first glance as a significant drawback in the realm of CCTP. In this perspective, we discuss this paradox and highlight the peculiar role played by Ni catalysts for CCTP reactions, both as polymerization and chain displacement catalysts, and highlight its implications for molecular and macromolecular engineering.