Acceleration of oxidation promoted by laccase irradiation with red light

Abstract

Irradiation with red light is able to improve yields and shorten the reaction time in enzymatic reactions. A commercially available laccase from Trametes versicolor, used in conjunction with a catalytic amount of TEMPO (20 mol%), was irradiated under red light (630 nm) for the clean oxidation of benzylic alcohols and amines in a faster reaction compared to the one conducted in the dark, affording the desired product in excellent yields (up to 99%) using air as the terminal oxidant. The observed acceleration is due to the strongest oxidation ability of laccase, in its excited state, towards TEMPO.