Photolysis of 1-bromo-2, 2-bis(p-alkoxyphenyl)-1-phenylethenes in the presence of sodium ethoxide in ethanol gave ipso adducts bearing 1,2-aryl rearranged structure, indicating that ipso substitution proceeds via vinylcations.
1-bromo-2, 2-bis(p-alkoxyphenyl)-1-phenylethenes 在乙醇中的乙醇钠存在下光解得到带有 1,2-芳基重排结构的 ipso 加合物,表明 ipso 取代是通过乙烯基阳离子进行的。