The chemistry of catalyst activation: The case of group 4 polymerization catalysts

Organometallic chemistry has provided the foundation for the development of a wide range of new olefin polymerization catalysts over the last two to three decades. The unraveling of the mechanisms of activation and the mode of action of polymerization catalysts has transformed these former “black-box” systems into some of the best understood catalysts to date. In recent years insight into mechanistic steps such as ligand exchange with main-group-metal alkyls has had particular far-reaching consequences for materials design and new industrial products. This review attempts to summarize the advances made over the last 9-10 years in our understanding of the chemistry of catalyst activation and associated fundamental mechanistic aspects.