Photolysis of β-(o-aryloxyphenyl)vinyl bromides in methylene chloride as well as solvolysis in 60% EtOH gave dibenz[b,f]oxepins exclusively by a new type of intramolecular cyclization of vinyl cations.
β-(邻芳氧基苯基)
乙烯基溴在
二氯甲烷中的光解以及在 60%
乙醇中的溶剂分解完全通过一种新型的
乙烯基阳离子分子内环化得到二苯并 [b,f] oxepins。