Base-free reaction of dichloroglyoxime with copper(i) acetylides gave 3,3′-biisoxazoles via a nucleophilic substitution of the chlorine atom of dichloroglyoxime with the acetylene moiety followed by cyclization of the intermediate formed. The effects of the solvent on the product yields were studied. In the case of substituted copper acetylides, 5,5′-disubstituted 3,3′-biisoxazoles were obtained in the yields from moderate to high and high regioselectivity.
二
氯乙二
肟与
铜(i)乙酰化物发生无碱反应,通过二
氯乙二
肟的
氯原子与
乙炔基团发生亲核取代反应,然后形成的中间体发生环化反应,生成 3,3′-双
异噁唑。研究了溶剂对产物产量的影响。在取代
铜乙酰化物的情况下,得到了 5,5′-二取代的 3,3′-联
异噁唑,产率从中等到高不等,并且具有很高的区域选择性。