Abstract
2, 4-Dimethyloxazole forms bromine adduct which changes to bromine substituted derivative at 135°. Nitration of this dimethyloxazole with nitric or nitric and sulfuric acids results in ring fission, showing that the reactivity of C5 to electrophilic reagents falls in the order or selenazole, thiazole, and oxazole. The reactivity at C5 increases in 2-diethylamino-4-methyloxazole and it undergoes coupling with diazonium compounds to form a labile azo compound. Condensation of 2, 4-dimethyloxazole and benzaldehyde gives 2-styryl compound and not 2, 4-distyryl derivative which shows that the reactivity of C2-position to nucleophilic reagent is higher than that of C4, this tendency being common with selenazoles and thiazoles.
