Synthesis of Indoles by Copper-Catalyzed Heteroannulation of o-Aminophenylboronic Acid Pinacol Esters with β-Keto Esters

Abstract

Copper-catalyzed coupling of o-aminophenylboronic acid pinacol esters with β-keto esters afforded, under mild base-free oxidative conditions, 2,3-disubstituted indoles featuring a key Chan–Lam-type carbon–carbon bond-forming reaction.

Key words

indole - copper catalysis - Chan–Lam reaction - o-amino­phenylboronic ester - β-keto ester

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