K₂S₂O₈-Mediated Arylmethylation of Indoles with Tertiary Amines via sp³ C–H Oxidation in Water

Abstract

A transition-metal- and catalyst-free, highly efficient synthesis of 3-arylmethylindoles has been achieved using tertiary amines as both methylene (-CH₂-) transfer and arylmethylation agents and K₂S₂O₈ as a convenient oxidant. The key feature of this protocol is the utilisation of K₂S₂O₈ as an inexpensive and easy to handle radical surrogate that can effectively promote the reaction, leading to the formation of C(sp²)–C(sp³)–C(sp²) bonds via sp³ C–H bond oxidation in water at room temperature in a one-pot procedure.

Key words

alkylation - indoles - tertiary amines - heterocycles - K₂S₂O₈ - radical oxidation

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