A recyclable and highly effective sulfamic acid/MeOH catalytic system for the synthesis of quinoxalines at room temperature

Sulfamic acid/MeOH has been used as an efficient and recyclable catalytic system for the synthesis of quinoxalines. The clean, mild acidity condition, quantitative yields of products, short reaction time and low reaction temperature are attractive features of this reaction which build a suitable method for heat- or acid-sensitive substrates, particularly in drug synthesis. In practice, this method is a combination of a satisfactory synthesis and, more significantly, easy product isolation and purification.