Intramolecular Addition of a Dimethylamino C(sp³)–H Bond across C–C Triple Bonds Using IrCl(DTBM-SEGPHOS)(ethylene) Catalyst: Synthesis of Indoles from 2-Alkynyl-N-methylanilines

Abstract

Intramolecular addition of a C(sp³)–H bond of the dimethylamino group across the C–C triple bond in 2-alkynyl-N,N-dimethylanilines is effectively catalyzed by a new iridium complex, IrCl(DTBM-SEGPHOS)(C₂H₄), in mesitylene at 150 °C. The intramolecular C(sp³)–H addition is followed by double-bond isomerization to afford 3-substituted indoles in good to high yields.

Key words

C–H bond activation - addition reaction - cyclization - iridium - indoles

Publication History

Received: 29 April 2021

Accepted after revision: 18 May 2021

Accepted Manuscript online:
18 May 2021

Article published online:
15 June 2021

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