Asymmetric Allylation, Crotylation, and Cinnamylation of N-Heteroaryl Hydrazones

A new class of N-heteroaryl hydrazones has been developed as an alternative to N-acylhydrazones and 2-aminophenol-derived imines in asymmetric allylation, crotylation, and cinnamylation reactions with chiral allylchlorosilanes. The hydrazones are readily and inexpensively prepared, perform well in the allylation chemistry, and more importantly, the product hydrazides may be smoothly reduced by Pd(OH)₂-catalyzed hydrogenation to reveal the corresponding amine products.