SYNTHESIS OF 2-ARYL AND 2-HETARYLOXAZOLES FROM THE OXAZOLINES AND OXAZOLIDINES

Article abstract of DOI:10.1007/BF00575249

Treatment of 2-phenyl-, 2-(2-furyl)-, and 2-(2-thienyl)oxazolines with nickel peroxide has been found to give, in addition to the dehydrogenation products (2-substituted oxazoles),the fragmentation products (amides of benzoic, furan-2-carboxylic, and thiophen-2-carboxylic acids).This fragmentation appears to give initially the nitriles, which are then converted into the amides by the nickel peroxide.Catalytic dehydrogenation of 2-phenyloxazoline gives low yields of 2-phenyloxazole, the principal product being benzonitrile.Treatment of the Schiff's bases obtained from ethanolamine and aldehydes (benzaldehyde, furfural, and thiophen-2-aldehyde) with nickel peroxide gives trace amounts of the oxazoles, the principal products being the aldehydes, with smaller amounts of the nitriles.