Benzyl group abstraction from Ti(CH2Ph)4 by B(C6F5)3 and [Ph3C][B(C6F5)4] to form Ziegler–Natta and carbocationic alkene polymerization initiators

Reaction of Ti(CH2Ph)4 with B(C6F5)3 results in the formation of [Ti(CH2Ph)3][(η6-PhCH2)B(C6F5)3], while reactions with [Ph3C][B(C6F5)4] give either [Ti(CH2Ph)3][B(C6F5)4] or [(CH2Ph)3Ti-μ-CH2PhTi(CH2Ph)3][B(C6F5)4], depending on the Ti(CH2Ph)4:[Ph3C] ratio; NMR evidence is presented that all of these compounds, including Ti(CH2Ph)4, exhibit multihapto Ti–CH2Ph bonding. The Ti(CH2Ph)4/B(C6F5)3 and Ti(CH2Ph)4/[Ph3C][B(C6F5)4] systems are assessed for their abilities to induce polymerization of ethylene, 1-hexene, isobutylene and ethyl vinylether, and the Ti(CH2Ph)4/[Ph3C][B(C6F5)4] system is found to be able to function as both a Ziegler–Natta catalyst and a carbocationic initiator.