Enantioselective and Catalytic Method for α‐Crotylation of Aldehydes with a Kinetic Self‐Refinement of Stereochemistry

Kinetic refinery: A practical, highly stereoselective, two-step catalytic protocol for the alpha-allylation of aldehydes, starting from crotyltrichlorosilanes, has been developed (see scheme). In each reaction step, one of the stereoisomers reacted faster than the other, which resulted in a kinetic stereochemical (E/Z) self-refinement of the system and led to the formation of virtually enantiomerically and geometrically pure linear homoallylic alcohols in high yield.