Thermolysis of diphenyl-Δ3- and diphenyl-Δ4-1,2,4-oxadiazolinones
Abstract
Thermolysis gave 2-phenylbenzoxazole from 2,3-diphenyl-Δ3-1,2,4-oxadiazolin-5-one and from 2,5-diphenyl-Δ4-1,2,4-oxadiazoline-3-one and also gave benzoxazolinone from the latter by new ring transformations which accompanied the formation of 2-phenylbenzimidazole and 2,4-diphenyl-Δ2-1,3,4-oxadiazolin-5-one as respective major products.