Highly efficient construction of 2,3-disubstituted indoline derivatives by [4 + 1] annulation of sulfur ylides and o -sulfonamido aldimines

Herein, it is reported that a formal [4 + 1] cycloaddition of o -sulfonamido aldimines and sulfur ylides has been successfully developed. This strategy led to a series of 2,3-disubstituted indoline derivatives with synthetical flexible carbonyl and sulfamide groups obtained with good yields and high diastereoselectivities. A variety of functional groups were well tolerated. It is worth noting that indoles could also be synthesized using this highly efficient cascade reaction.