Sulfur-mediated annulation of 1,2-phenylenediamines towards benzofuro- and benzothieno-quinoxalines

Org Biomol Chem. 2020 Aug 7;18(29):5652-5659. doi: 10.1039/d0ob00887g. Epub 2020 Jul 10.

Abstract

We report a method for condensation between ortho-phenylenediamines and ortho-hydroxyacetophenones to afford benzofuroquinoxalines. The reactions proceeded in the presence of an elemental sulfur mediator, DABCO base, and DMSO solvent. Functionalities such as nitrile, ester, and halogen groups were compatible. The conditions could be applicable for the synthesis of benzothienoquinoxalines from ortho-chloroacetophenones.

Publication types

  • Research Support, Non-U.S. Gov't