Synthesis of benzo[g]chrysene 5,6-oxide and 7,8-oxide and their isomeric oxepines

Abstract

Benzo[g]chrysene 5,6-oxide and benzo[g]chrysene 7,8-oxide when synthesised from dibromo acetate precursors were accompanied by the stable oxepine isomers benzo[3,4] phenanthro[2,1-b]-oxepine and benzo[3,4]phenanthro[1,2-b]oxepine. The isolation of the latter oxepines, and their formation by photochemichal rearrangement of the isomeric arene oxides, are in accord with earlier predictions from PMO calculations.