Supported Bifunctional Chiral Thioureas as Catalysts in the Synthesis of 3‐Amino‐2‐Oxindoles through Enantioselective aza‐Friedel‐Crafts Reaction: Application in Continuous Flow Processes

Abstract

Supported cinchone‐derived thioureas promote highly enantioselective aza‐Friedel‐Crafts reaction of different naphthols with a variety of N‐Boc ketimines derived from isatin. The catalysts are recoverable and reusable, and one of the supported catalysts has been used in a flow process allowing the synthesis of 3‐amino‐2‐oxindole derivatives in multigram scale with high yield and enantioselectivity.