Olefin polymerization by pentamethylcyclopentadienyl trimethyltitanium, Cp*TiMe3

The compound Cp*TiMe3 can be activated with a variety of Lewis and Bronsted acids to generate precursors of the cationic species [Cp*TiMe2](+). The la tter can serve as an initiator for (a) the polymerization of ethylene and a lpha-olefins via epsilon(2) coordination and a Ziegler-Natta process, (b) t he ring opening metathesis polymerization of norbornene and the cyclopolyme rization of 1,5-hexadiene, and (c) the polymerization of styrene, vinyl eth ers, N-vinyl carbazole and isobutylene via epsilon(1) coordination and a ca rbocationic process. In addition, an as yet undefined product of decomposit ion of [Cp*TiMe2](+) catalyzes the polymerization of styrene to highly ster eoregular syndiotactic polystyrene.