Copper-Catalyzed Enantioselective Formation of C-CF3 Centers from ß-CF3 -Substituted Acrylates and Acrylonitriles.

The catalytic asymmetric synthesis of ß-trifluoromethylated esters or nitriles is reported. The use of an in situ formed chiral Cu-H complex allowed the enantioselective reduction of ß-trifluoromethylated acrylates or acrylonitriles. The reaction proceeds smoothly affording the corresponding enantioenriched products in good to excellent yields and outstanding enantioselectivities (up to 98 % ee). The mechanism of the reaction was studied, and a plausible reaction pathway was suggested accordingly. Finally, the versatility of the products was highlighted through functional group manipulations.

Stereoselective Synthesis of Terminal Monofluoroalkenes from Trifluoromethylated Alkenes.

Herein we report the hydrodefluorination reaction of trifluoromethylated alkenes to access terminal monofluoroalkenes. The use of LiAlH4 allowed the stereoselective synthesis of the terminal monofluoroalkenes in good to excellent yields with good to excellent diastereoselectivities. Mechanistic studies suggested a hydroalumination reaction followed by a stereoselective fluoride elimination.