Synthesis of 2-Arylquinoxalines from Sulfoxonium Ylides in the Absence of Sacrificial Electrophile and Base

Abstract

We report a method for the annulation of 1,2-phenylenediamines and aryl sulfoxonium ylides to yield 2-arylquinoxalines. Known conditions often require sacrificial electrophiles, an oxidative solvent (i.e., DMSO), and an overstoichiometric amount of base. Herein, conditions including the use of the catalytic amount of Bu4NI and m-xylene solvent to facilitate the formation of 2-arylquinoxalines in good to excellent yields have been developed. Functionalities including halogens, protected phenol, and secondary amine groups were tolerant.

Keywords

Annulation - Phase transfer catalyst - Quinoxalines - Sulfoxonium ylides - Electrophile-free

Publication History

Received: 02 June 2025

Accepted after revision: 03 August 2025

Accepted Manuscript online:
04 August 2025

Article published online:
26 August 2025

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