Unexpected Reduction of Ethyl 3-Phenylquinoxaline-2- carboxylate 1,4-Di-N-oxide Derivatives by Amines
作者:Lidia Lima、Esther Vicente、Beatriz Solano、Silvia Pérez-Silanes、Ignacio Aldana、Antonio Monge
DOI:10.3390/molecules13010078
日期:——
The unexpected tendency of amines and functionalized hydrazines to reduceethyl 3-phenylquinoxaline-2-carboxylate 1,4-di-N-oxide (1) to afford a quinoxaline 1c andmono-oxide quinoxalines 1a and 1b is described. The experimental conditions werestandardized 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 thechemoselectivity of the process. With the exception of hydrazine hydrate, which reducedcompound 1 to a 3-phenyl-2-quinoxalinecarbohydrazide derivative, the amines only actedas reducing agents.
本文描述了胺和官能化肼在还原 3-苯基喹喔啉-2-甲酸乙酯 1,4-二-N-氧化物(1)时产生喹喔啉 1c 和单氧化物喹喔啉 1a 和 1b 的意想不到的趋势。我们将实验条件标准化为在乙醇中使用两当量的胺,并回流两小时,目的是研究胺的不同还原性特征以及该过程的化学选择性。除了将化合物 1 还原成 3-苯基-2-喹喔啉羧酰肼衍生物的水合肼之外,其他胺都只起还原剂的作用。