Enantioselective Allylation of Ketone-Derived Benzoylhydrazones: Practical Synthesis of Tertiary Carbinamines

A highly practical method for the enantioselective allylation of ketone-derived benzoylhydrazones has been developed. The previously reported strained silacycle reagent 1 reacts with a wide variety of benzoylhydrazones to give the hydrazide products with good to excellent enantioselectivity (84−97% ee). A mechanism in which the acylhydrazone becomes caovalently attached to the silane has been established.