Rh(I)-catalyzed enantioselective (3 + 2) transannulations of 1,2,3-thiadiazoles with P-chiral monodentate phosphines

Abstract

As a proof of concept, P-chiral monodentate phosphines, which were inactive in promoting the transannulations of 1,2,3-thiadiazoles, were proven viable in the asymmetric catalytic (3 + 2) transannulations of 1,2,3-thiadiazoles with a strained bicyclic alkene. Polycyclic dihydrothiophenes with four newly formed stereocenters are generated in moderate 19-72% yields and 11-27% enantiopurities.