Rh-catalyzed kinetic resolution of enynes and highly enantioselective formation of 4-alkenyl-2,3-disubstituted tetrahydrofurans

Abstract

Rh-catalyzed cycloisomerization of enynes ether with a substituent at the allylic position was examined using (rac)-BINAP, and excellent selectivity was observed. When enantiomerically pure BINAP was used as the ligand, a process that combines kinetic resolution and diastereoselectivity together was developed, in which an enantiomeric product with multiple stereogenic centers was obtained in >99% ee from a racemic starting material via single step, and half of the remaining starting material was recovered in >99% ee, also.