A Golden Synthetic Approach to 2-(1H-Pyrrol-1-yl)anilines and Pyrrolo[1,2-a]quinoxalines through a Gold Carbene Intermediate

Abstract

The pyrrolo[1,2-a]quinoxaline skeleton has significant potential for many biological and optical applications. Hence, in this study, unconjugated ynone derivatives were treated with 1,2-diaminoarenes in a gold-catalyzed cyclization to give 2-(1H-pyrrol-1-yl)anilines, which are valuable starting materials, and pyrrolo[1,2-a]quinoxalines by a one-pot and single-step approach. A reaction mechanism for the formation of the pyrrolo[1,2-a]quinoxaline skeleton featuring a key gold carbene intermediate is proposed. On the other hand, the methyl group on the C-2 position of the 2-(1H-pyrrol-1-yl)anilines was oxidized by SeO₂ to give the pyrrolo[1,2-a]quinoxaline skeleton, resulting in 14 different pyrrolo[1,2-a]quinoxaline derivatives.

Keywords

pyrroloquinoxalines - diaminoarenes - pyrrolylanilines - gold catalysis - cyclization - oxidation

Publication History

Received: 25 August 2022

Accepted after revision: 24 August 2023

Accepted Manuscript online:
24 August 2023

Article published online:
31 October 2023

• References and Notes

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