Neutral, Cationic and Hydride‐substituted Siloxygermylenes

Abstract

The introduction of the labile trimethylsiloxy group to Ge^II centers in the presence of an N-heterocyclic carbene donor is reported. The new complex IPr⋅GeCl(OSiMe₃ ) (IPr=[(HCNDipp)₂ C:]; Dipp=2,6-iPr₂ C₆ H₃ ) was readily converted into the structurally unique Ge^II siloxy(hydrido)germylene IPr⋅GeH(OSiMe₃ )⋅BH₃ by treatment with lithium borohydride. Additionally, the reactive siloxygermylene cation [IPr⋅Ge(OSiMe₃ )]⁺ was synthesized and clean oxidative addition of CH₂ Cl₂ was demonstrated. The two-coordinate [IPr⋅Ge(OSiMe₃ )]⁺ cation also promoted the catalytic hydroborylation of sterically hindered ketones under mild conditions, with enhanced reactivity stemming from an open coordination site at Ge.