Formation of 4-p-Bromophenyl-5-hydroxy-3-methoxycarbonyl-5, 6-dihydro-4H-1, 2-oxazine by Means of New Ring Transformation of an Isoxazoline-2-oxide

Abstract

4-p-Bromophenyl-5-hydroxymethyl-3-methoxycarbonyl-2-isoxazoline-2-oxide methanesulfonate (1c) reacted with excess titanium tetrabromide in dichloromethane to yield a novel ring transformation product, 4-p-bromophenyl-5-hydroxy-3-methoxycarbonyl-5, 6-dihydro-4H-1, 2-oxazine (2). The structural determination of 2 by single-crystal X-ray analysis is reported.