A green synthetic approach to construct C2‐quaternary indolin‐3‐ones at room temperature via regioselective oxidative dearomatization of indoles

Abstract

A new synthetic strategy for the construction of C2‐quaternary indole for the formation of Indolin‐3‐ones has been explored via indium(III) trifluoromethansulphonate catalyst at room temperature with TBHP as a green oxidant in water. This approach for the oxidative dearomatization process allows to produce natural product Halichrome A and a broad range of C2‐arylated Indolin‐3‐ones under a milder condition in very good yields. The oxidative self‐dimerization and self‐trimerization of various indole derivatives have also been achieved under the same conditions.