Asymmetric Synthesis of SCF₃‐Substituted Alkylboronates by Copper‐Catalyzed Hydroboration of 1‐Trifluoromethylthioalkenes

A synthetic method for preparation of optically active trifluoromethylthio (SCF 3 ) compounds by a copper‐catalyzed regio‐ and enantioselective hydroboration of 1‐trifluoromethylthioalkenes with H‐Bpin has been developed. The enantioselective hydrocupration of an in situ generated CuH species and subsequent boration reaction generate a chiral SCF 3 ‐containing alkylboronate, of which Bpin moiety can be further transformed to deliver various optically active SCF 3 molecules. Computational studies suggest that the SCF 3 group successfully controls the regioselectivity in the reaction.