Trivalent Rare‐earth Metal Amide Complexes as Catalysts for Hydrosilylation of Benzophenone Derivatives with HN(SiHMe2)2 via Amine Exchange Reaction

The rare-earth metal complexes Ln( L 1 )[N(SiHMe 2 ) 2 ](thf) (Ln = La, Ce, Y; L 1 = N , N'' -bis(pentafluorophenyl)diethylenetriamine dianion) were synthesized by treating Ln[N(SiHMe 2 ) 2 ] 3 (thf) 2 with L 1 H 2 . The lanthanum and cerium derivatives are active catalysts for the hydrosilylation of benzophenone derivatives with HN(SiHMe 2 ) 2 . An amine exchange reaction was revealed as a key step of the catalytic cycle, where Ln---Si-H β-agostic interactions are proposed to promote insertion of the carbonyl moiety into the Si-H bond.