New binuclear alkyl and half-sandwich cyclopentadienyl imido titanium complexes containing acetamidinate and benzamidinate supporting ligands

Chloride metathesis reactions of the binuclear titanium N,N'-bis(cyclohexyl)acetamidinato-mu-imido compound [Ti-2(mu-NBut)(2){MeC(NC6H11)(2)}(2)Cl-2] (1) and the mononuclear N,N'-bis(trimethylsilyl)benzamidinato-imido analogue [Ti(N-Bu-t){PhC(NSiMe3)(2)}Cl(py)(2)] (2) are described. Thus, reaction of 1 or 2 with LiC5R5 (R = H or Me) gave the half-sandwich compounds [Ti(NBut){MeC(NC6H11)(2)}(eta-C5H5)] and [Ti(NBut){PhC(NSiMe3)(2)}(eta-C5Me5)], respectively. These compounds are also accessible from [Ti(NBut)(eta-C5R5)Cl(L)] (R = H or Me; L = py or 4-NC5H4But) and the appropriate lithium amidinate. Treatment of 1 with MeLi gave the binuclear 12-electron methyl derivative [Ti-2(mu-NBut)(2){MeC(NC6H11)(2)}(2)(Me)(2)] which has been crystallographically characterised. (C) 1998 Elsevier Science S.A. All rights reserved.