Previous Article in event
Next Article in event
Unexpected Reduction of Ethyl 3-phenylquinoxaline-2-carboxylate 1,4-di-N-oxide Derivatives by Amines
Published: 30 November 2007 by MDPI in The 11th International Electronic Conference on Synthetic Organic Chemistry session General Organic Synthesis
Abstract: The unexpected tendency of amines and functionalized hydrazines to reduce the ethyl 3-phenylquinoxaline-2-carboxylate 1,4-di-N-oxide (1) to a quinoxaline (1c) and mono-oxide quinoxalines (1a and 1b) is described. The experimental conditions were standardized in the use of 2 equivalents of amine in ethanol under reflux for 2 hours, with the aim of studying the distinct reductive profile 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.
Keywords: quinoxaline N-oxides, reduction, carboxylate, amines