3-Tetrasubstituted oxindoles have attracted significant attention of some synthetic and medicinal chemistry communities because of the prevalence of them in a wide variety of structurally complex and biologically active compounds. In particular, 3,3′-disubstituted oxindoles with β-amino functionality are a key structural feature of several classes of pharmaceuticals and natural products and are extremely versatile building blocks that can undergo synthetically useful transformations.

The development of efficient synthetic methods for the asymmetric stereocontrolled construction of 3,3′-disubstituted oxindoles bearing β-amino functionality would be especially desirable.Therefore, in view of the high nucleophilicity of the oxindole 3-position.

For a recent review relating to the application of oxindoles as nucleophiles and the high potential to rapidly increase molecular complexity as well as the rich chemistry of the nitro group, the catalytic asymmetric conjugate addition of 3-substituted oxindoles to nitroolefins represents one of the most powerful and straightforward approaches toward optically active 3,3′-disubstituted oxindoles with β-amino functionality and has understandably attracted great synthetic interest.

A simple catalyst system assembled from an enantiomerically pure diamine ligand and Ni(OAc)(2) efficiently generates chiral metal enolates derived from 3-substituted oxindoles bearing an N-1 carbonyl group. The enolates smoothly undergo diastereo- and enantioselective conjugate addition to a wide range of nitroolefins under mild reaction conditions, furnishing 3,3-disubstituted oxindole products bearing two vicinal quaternary/tertiary stereocenters in 74-95% yields and 60:40 to 99:1 dr, 71-97% ee.

Researchers from CAS Chengdu Institute of Organic Chemistry cooperated with  CAS Chengdu Institute of Biology  to study this job and it has been supported by National Natural Science Foundation of China  and National Basic Research Program of China (973 Program) .