Dehydrogenative coupling reactions catalysed by Rose Bengal using visible light irradiation

Abstract

Rose Bengal, an organic dye, was demonstrated to be a photoredox catalyst for dehydrogenative coupling reactions using visible light irradiation. α-Functionalised tertiary amines were obtained with good to excellent yields. Air is essential for this reaction and acts as the terminal oxidant. This is an environmentally friendly C–H functionalisation methodology that avoids the use of metal catalysts and stoichiometric amount of peroxo-compounds.