Synthesis, solid state and DFT structure and olefin polymerization capability of a unique base-free dimeric methyl titanium dication

Abstract

Reaction of Cp*Ti{NC(ArF2)NiPr2}Me2 (1, ArF2 = 2,6-C6H3F2) with [Ph3C][B(C6F5)4] gave the base-free structurally authenticated dication [Cp*2Ti2{NC(ArF2)NiPr2}2(μ-Me)2][B(C6F5)4]2 (3-[BF20]2) containing two doubly α-agostic bridging methyl groups. 3-[BF20]2 is a highly effective ethylene–propylene polymerization catalyst at 90 °C, and its performance is identical to the catalyst generated in situ from 1 and [Ph3C][B(C6F5)4].