Furazan ring opening upon treatment of benzofurazan with ethanolamine to yield quinoxalines

摘要

Heating of benzofurazans with ethanolamine in the presence of catalytic amount of p-toluenesulfonic acid leads to quinoxalines.Study of chemical properties of benzofurazans showed that the heating of compounds 1a-g with ethanolamine at 150-170 °C in the presence of catalytic amount of p-toluenesulfonic acid unexpectedly leads to quinoxalines 2a-g (Scheme 1).