A catalyst-free bis(triflyl)ethylation/benzannulation reaction: rapid access to carbazole-based superacidic carbon acids from alkynols

Abstract

A metal- and irradiation-free preparation of Tf₂CHCH₂-decorated carbazoles from 1-(indol-2-yl)but-3-yn-1-ols under mild conditions with a 2-fluoropyridinium salt as the Tf₂CCH₂ source has been attained in a straightforward and selective manner.