Regioselective Access to Sultam Motifs through Cobalt‐Catalyzed Annulation of Aryl Sulfonamides and Alkynes using an 8‐Aminoquinoline Directing Group

Abstract

Abstract The use of cobalt as catalyst in direct CH activation protocols as a replacement for more expensive second row transition metals is currently attracting significant attention. Herein we disclose a facile cobalt‐catalyzed CH functionalization route towards sultam motifs through annulation of easily prepared aryl sulfonamides and alkynes using 8‐aminoquinoline as a directing group. The reaction shows broad substrate scope with products obtained in a highly regioselective manner in good to excellent isolated yields. Mechanistic insights suggest the formation of a Co(III)‐aryl key species via a rate‐determining arene CH activation during the annulation reaction. magnified image