Synthesis 2021; 53(17): 3057-3064
DOI: 10.1055/a-1511-1025
special topic
Bond Activation – in Honor of Prof. Shinji Murai

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

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Kaito Yagi
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This work was partially supported by Japan Society for the Promotion of Science (JSPS KAKENHI Grant Numbers JP20H05674 and JP21H01937), by Asahi Glass Foundation, and by Tonen General Sekiyu Research/Development Encouragement and Scholarship Foundation.


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.

Supporting Information



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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