Highly enantioselective organocatalytic sulfenylation of 3-aryloxindoles.

An organocatalytic asymmetric sulfenylation of 3-aryloxindoles with N-(sulfanyl)succinimides has been developed by using commercially available (DHQD)(2)PHAL as catalyst. Various chiral 3-benzylthio-, alkylthio-, and arylthio-substituted oxindoles, containing 3,3-disubstituted quarternary carbon stereocenters, could be obtained in high enantioselectivities (85-97% ee). Furthermore, the opposite enantiomers of the sulfenylated products were readily accessible with equal excellent enantioselectivities (86-95% ee) by replacing the catalyst with (DHQ)(2)PHAL.