Studies on Azole Compounds. II. Reaction of Oxazole N-Oxides with Phenylisocyanate to give Imidazole Derivatives

Abstract

The reactions of 4-methyloxazole N-oxides substituted in the 2-position (Ia-d) with phenylisocyanate were studied. The oxazole N-oxides were easily attacked on the 2-position by the nitrogen of phenylisocyanate, followed by ring-cleavage and re-cyclization to give 5-hydroxy-4-methylene-1, 2, 5-trisubstituted 4, 5-dihydroimidazoles (IIa-d). The structures of IIa-d were determined by their chemical behavior and spectral data.