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

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-(Pr2C6H3)-Pr-i) is reported. The reaction gives the scandium anilido hydride [LSc(H)(N(DIPP)(SiH2Ph))] (2), and a labeling experiment shows a rapid sigma-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))(kappa(2)(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 degrees C with 5 mol % of catalyst loading and highly selectively produced the monoaminosilane.