[3 + 2] cycloaddition for the assembly of indolizine-based heterocyclic sulfonyl fluorides

Abstract

Presented herein is a method for the construction of indolizine-based heterocyclic sulfonyl fluorides through [3 + 2] cycloaddition of isoquinolinium/quinolinium salts and 1-bromoethene-1-sulfonyl fluoride (BESF), driven by Et₃N and 4,5-dichloro-3,6-dioxocyclohexa-1,4-diene-1,2-dicarbonitrile (DDQ). This transformation features mild conditions, high efficiency, easily obtained starting materials, and broad substrate scope, providing a great potential value in medicinal chemistry and other related disciplines.