Abstract
Treatment of 10-halogeno-2, 3, 5, 6, 7, 11b -hexahydro -7-methyl-11b-phenylbenzo [6, 7]-1, 4-diazepino [5, 4-b] oxazol-6-one (IIIa-d) with dimethyl formamide in the presence of sodium hydride gave exo -methylene compounds (Va-d). On the other hand, the compounds (IIIe-g) having halogen at o-position of the 11b-phenyl group gave no exomethylene compounds, but isoindoles (XVIIIe-g) and acridanone derivatives (XIXe-g). A mechanistic assumption for the formation of these compounds from benzo [6, 7]-1, 4-diazepino [5, 4-b] oxazole derivatives was given.
