Enantioselective Desymmetrization of Prochiral Cyclopentene-1,3-diones Triggered by Remote C(sp2)-N Bond Formation.

The enantioselective desymmetrization via remote C(sp2)-H amidation of the prochiral 2,2-disubstituted cyclopentene-1,3-dione with N-methoxybenzamide has been developed. The overall process was catalyzed by a chiral bifunctional thiourea catalyst through a sequential conjugate-addition-elimination-tautomerization. This strategy provides rapid access to highly functionalized five-membered carbocycles, bearing an all-carbon quaternary stereogenic center through remote stereocontrol in high yields with moderate to excellent enantioselectivities.