Acid-catalyzed rearrangement of 2-phenyl-2,3-dihydro-1,4-benzoxazepin-5(4H)ones

2-Phenyl-2,3-dihydro-1,4-benzoxazepin-5(4H)ones (I) were converted into 2-(o-hydroxyaryl)-5-plienyl-2-oxazolines (II) and 3,4-diliydro-4-plienyl-8-hydroxyisoearbostyrils (III) by concentrated sulfuric acid. The ratio of II and III is dependent upon substituents present in the aromatic ring of the parent benzoxazepinones.