Reversible Addition of the Si–H Bond of Phenylsilane to the Sc═N Bond of a Scandium Terminal Imido Complex

Abstract

The facile and reversible addition of the Si–H bond of phenylsilane to the Sc═N bond of the scandium terminal imido complex [LSc═NDIPP(DMAP)] (1; L ═ [MeC(N(DIPP))CHC(Me)(NCH2CH2NMe)]−, DIPP = 2,6-iPr2C6H3) is reported. The reaction gives the scandium anilido hydride [LSc(H)(N(DIPP)(SiH2Ph))] (2), and a labeling experiment shows a rapid σ-bond metathesis between Sc–H of the formed scandium anilido hydride and Si–H of phenylsilane during the reaction. 2 was trapped by an insertion reaction with diphenylcarbodiimide, giving the stable scandium anilido amidinate [LSc(N(DIPP)(SiH2Ph))(κ2(N,N′)-PhNCHNPh)] (3). Furthermore, the scandium terminal imido complex can efficiently catalyze the hydrosilylation of N-benzylidenepropan-1-amine. The reaction was completed within 2 h at 50 °C with 5 mol % of catalyst loading and highly selectively produced the monoaminosilane.