Enantioselective Synthesis of 3-Substituted 3-Amino-2-oxindoles by Amination with Anilines

chiral N,N'-dioxide-nickel(II) complex-catalyzed asymmetric amination of 3-bromo-3-substituted oxindoles with anilines has been developed. A series of alkyl or aryl 3-amino-indolinones with quaternary stereocenters were obtained in high yields with excellent ee values in one step (up to 99% yield, up to 96% ee). The method provided a ready route to optically active intermediates of 3-amino-2-oxindole-based bioactive compounds. Moreover, a possible transition-state model is proposed so as to elucidate the origin of the chirality based on the X-ray crystal structure of the catalyst and the adduct.

Automated summary

In this study, a chiral N,N'-dioxide-nickel(II) complex-catalyzed asymmetric amination method was developed for the synthesis of alkyl or aryl 3-amino-indolinones with quaternary stereocenters in high yields with excellent ee values. The proposed method offers a convenient route to optically active intermediates of 3-amino-2-oxindole-based bioactive compounds, and a possible transition-state model was proposed to elucidate the origin of the chirality based on the X-ray crystal structure of the catalyst and the adduct.