Reactions of α,N-Diarylnitrones with O-Methyl Diphenylphosphinothioate and Oxidations of N-Alkylidene-2-hydroxyanilines with Silver Oxide. Preparation of Benzoxazoles

Article abstract of DOI:10.1246/bcsj.55.873

Reactions of α,N-diarylnitrones in the presence of O-methyl diphenylphosphinothioate at 150 deg C gave 2-arylbenzoxazoles (3) in fairly good yields.Oxidation of N-alkylidene-2-hydroxyanilines with silver oxide afforded 2-alkenyl-, 2-alkyl-, or 2-arylbenzoxazoles (7 and 3) in good yields under mild reaction conditions (at room temperature).A plausible mechanism for formation of 3 and 7 has been discussed briefly.