Conclusive Evidence for an S_N2-Si Mechanism in the B(C6F5)3-Catalyzed Hydrosilylation of Carbonyl Compounds:Implications for the Related Hydrogenation

摘要

The precise mechanistic understanding of chemical transformations is an urgent challenge in synthetic chemistry as it guides the targeted design of improved or even novel processes.For example,transition-metal-free reduction of C=X bonds(X=O and NR)catalyzed by boroh-based Lewis acids is currently attracting considerable attention.Illuminating its mechanism(s)of action might open the door for the development of yet unknown enantioselective variants.In this context,commercially available tris(pentafluorophenyl)bor-ane(1)is a particularly effective catalyst for both hydrosilylation and hydrogenation.