3-Arylidenebenzofuran-2(3H)-ones are obtained by condensation of aldehydes Ar1CHO with benzofuran-2(3H)-one. A mixture of stereoisomers (Z) and (E) was isolated. The reaction of diarylnitrilimines with the Z+E mixture or with each stereoisomer leads regio- and stereoselectively to cycloadducts which give, after acidic treatment, the same 5,6-diaryl-4-(o-hydroxyphenyl)pyridazin-3(2H)-one 6, irrespective of the double bond geometry of the starting olefin.
3-Arylidenebenzofuran-2(3H)-ones 是通过醛 Ar1CHO 与
苯并呋喃-2(3H)-酮缩合得到的。分离出立体异构体(Z)和(E)的混合物。二芳基硝基
亚胺与 Z+E 混合物或每种立体异构体发生反应,可产生具有区域和立体选择性的环加成物,这些环加成物经酸性处理后可得到相同的 5,6-二芳基-4-(邻羟基苯基)
哒嗪-3(2H)-酮 6,与起始烯烃的双键几何形状无关。