Synthesis of 1,4-dihydro-benzo[d][1,3]oxazin-2-ones from phthalides via an aminolysis-Hofmann rearrangement protocol

A simple two-step procedure for the conversion of readily available phthalides to the corresponding benzoxazinones was developed. Initial ring-opening aminolysis to form a primary 2-hydroxymethylbenzamide, followed by reaction with bis(trifluoroacetoxy)iodobenzene (BTI) conveniently, provided a variety of 4-substituted benzoxazinones.