Room-temperature and ambient-pressure conversion of renewable carbohydrates to value-added aromatic N-heterocycles under ultrasonic irradiation conditions

Abstract

We report a new approach that allows highly efficient one-step conversion biomass-derived carbohydrates to high-value 2-methylquinoxalines in the presence of aryl-1,2-diamines in water at room temperature and under ambient pressure. A joint effect from ultrasound and strong alkali is revealed as the key for enabling this transformation. Various carbohydrates and diverse aryl-1,2-diamines verified the efficient and selective production of various 2-methylquinoxalines (up to 83 C% yield) under mild conditions. More importantly, a novel integrated chemo-enzymatic process, based on the enzymatic catalytic degradation of cellulose and ultrasound-enabled chemical transformation of glucose, is proposed for the direct conversion of recalcitrant cellulose to 2-methylquinoxalines under near room-temperature conditions.