| 總結: | The unexpected tendency of amines and functionalized hydrazines to reduce
ethyl 3-phenylquinoxaline-2-carboxylate 1,4-di-N-oxide (1) to afford a quinoxaline 1c and
mono-oxide quinoxalines 1a and 1b is described. The experimental conditions were
standardized to the use of two equivalents of amine in ethanol under reflux for two hours,
with the aim of studying the distinct reductive profiles of the amines and the
chemoselectivity of the process. With the exception of hydrazine hydrate, which reduced
compound 1 to a 3-phenyl-2-quinoxalinecarbohydrazide derivative, the amines only acted
as reducing agents.
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