Reversible Formation of a Cerium‐Bound Terminal Hydride: Ce(C5Me4SiMe3)2(H)(thf)

Abstract

The use of the bulky cyclopentadienyl ligand Cp′ (Cp′ = C5Me4SiMe3) to stabilize cerium hydrides has resulted in the preparation of two novel tuck‐in complexes with C–H activated SiMe3 groups. Subsequent reaction of these with H2 in thf gives a lanthanide terminal hydride species Ce(Cp′)2(H)(thf) which reversibly regenerates the tuck‐in complex under sustained vacuum. This compound is only the second structurally characterized terminal cerium hydride. This new hydride is a catalyst in H/D exchange reactions between with both sp3‐CH and sp2‐CH bonds, and for the hydrogenation of unsaturated alkene bonds.