Contrary to what is observed with other π-deficient heteroaromatic N-oxides, the reaction of 2, 3-diphenylquinoxaline-N1-oxide with OPCl3 gives only very poor yields of chlorinated quinoxalines. It is shown that the major product arises from an unprecedented attack by the nucleophilic oxygen atom of the reagent at a carbon atom of the homocycle of the O-phosphorylated N-oxide, leading ultimately to
与其他π-缺陷杂芳族N-氧化物所观察到的相反,2,3-二苯基
喹喔啉-N 1-氧化物与OPCl 3的反应仅产生非常差的
氯化
喹喔啉收率。结果表明,主要产物来自于试剂的亲核氧原子对O-
磷酸化N-氧化物的同环碳原子的空前攻击,最终导致相应的单(或二)芳基酯
磷酸。使用少得多的过量的OPCl 3并用惰性溶剂稀释
培养基会大大提高
氯化产物的收率。