Zinc-Catalyzed Synthesis of Allylsilanes by Si-H Bond Insertion of Vinyl Carbenoids Generated from Cyclopropenes.

Allylsilanes have long been recognized as valuable building blocks for organic synthesis. A zinc-catalyzed reaction of cyclopropenes and hydrosilanes provides a convenient route to these versatile unsaturated organosilanes. In this transformation, ZnBr2 serves as an efficient catalyst, allowing the generation of a zinc vinyl carbenoid intermediate, which is subsequently involved in a Si-H bond insertion. The process shows broad scope, and is amenable to substituted and functionalized cyclopropenes or the functionalization of polysiloxanes. Moreover, zinc-catalyzed carbene insertion into a Ge-H bond is reported for the first time.