Cycloaddition Reactions of the Titanium Imide [Ti(NBut){MeC(2-C5H4N)(CH2NSiMe3)2}(py)] with ButCP and MeCN

The diamidopyridine-supported titanium imide [Ti(NBut)(L)(py)] [1, L = MeC(2- C5H4N)(CH2NSiMe3)2] undergoes a [2+2] cycloaddition reaction with ButCP to form the mononuclear product [Ti{N(But)PC(But)}(L)] (2). In contrast, reaction of 1 with MeCN affords the binuclear derivative [Ti2{μ-η2-NC(Me)NBut}2(L)2] (3), which contains a doubly deprotonated N-tert-butylacetamidinate ligand. Compound 3 undergoes a quantitative cycloreversion reaction at elevated temperatures yielding MeCN and [Ti(NBut)(L)] (4).