Lithium hydroxide mediated synthesis of 3,4-disubstituted pyrroles

Abstract

LiOH·H₂O in ethanol was found to be an effective reagent for the synthesis of 3,4-disubstituted pyrrole derivatives by the van Leusen method. In situ formation of chalcones from aromatic aldehydes and enolisable ketones, and their subsequent reaction with tosylmethyl isocyanide resulted in the formation and precipitation of pyrrole derivatives from the reaction medium, in good yields. The solvation effect of the polar medium facilitates the reaction.