Synthesis of Highly Substituted 3-Acylpyrroles by a Four-Component Sonogashira Alkynylation–Amine Addition–Nitroalkene Michael Addition–Cyclocondensation

Abstract

A consecutive four-component alkynylation-amine addition-nitroalkene addition-cyclocondensation one-pot reaction of acid chlorides, alkynes, amines and nitroalkenes furnishes a library of 3-acyl pyrroles in modest to good yields. The sequence takes advantage of a synergism between Brønsted acid (acetic acid) and Lewis acid (iron(III) chloride) in the terminal addition-cyclocondensation step of the intermediary formed enaminones with nitroalkenes.