Abstract An attempt to prepare azirines by the base-catalyzed rearrangement of some quaternary hydrazones gave the corresponding azirine derivatives. Namely, 2-phenyl-3-methylazirine was obtained by the treatment of propiophenone dimethylhydrazone methiodide with potassium t-butoxide, but treatment with sodium isopropoxide gave 2,5-diphenyl-3,6-dimethylpyrazine or 2-phenyl-2-isopropoxy-3-methylaziridine, depending on the reaction conditions. 2-Phenyl-3,3-pentamethyleneazirine was obtained in a good yield by the treatment of cyclohexyl phenyl ketone dimethylhydrazone methiodide with sodium isopropoxide.