Direct catalytic synthesis of densely substituted 3-formylpyrroles from imines and 1,4-ketoaldehydes

Abstract

A sustainable method for the direct access to highly substituted 3-formylpyrroles from 1,4-ketoaldehydes and imine via formal [3 + 2] cycloaddition is reported. This reaction involves a one-pot amine catalyzed chemoselective Mannich-cyclization-aerobic oxidation sequence with good to high yields. Further application of the gram scale reaction as well as synthesis of fully substituted 3-formylpyrrole is also shown.