Base-Promoted Formal Arylation of Benzo[<i>d</i>]oxazoles with Acyl Chloride

Abstract

A base-promoted formal arylation of benzo­[<i>d</i>]­oxazoles with acyl chloride was achieved in moderate to good yields. This reaction was triggered by the <i>N</i>-acylation of oxazole to form an iminium intermediate. Then, the addition of H₂O to the iminium formed the hemiacetal intermediate. After the sequential ring-opening, extrusion of CO, the ring closure, the dehydration delivered the formal arylation product. In comparison with the transition-metal-catalyzed methodology, it represents an alternative arylation method leading to 2-arylbenzooxazole