The regiospecific Fischer indole reaction in choline chloride·2ZnCl₂with product isolation by direct sublimation from the ionic liquid

Abstract

The Fischer indole synthesis occurs in high yield with one equivalent of the ionic liquid choline chloride[middle dot]2ZnCl(2); exclusive formation of 2,3-disubstituted indoles is observed in the reaction of alkyl methyl ketones, and the products readily sublime directly from the ionic liquid.