PURPOSE: To obtain various aziridine ketone compounds in high yields by addition-reacting an O-alkyl hydroxylamine to an easily available α,β-unsaturated ketone, and subsequently treating the obtained β-alkoxyaminoketone with a base in a specific solvent.

CONSTITUTION: A β-alkoxyaminoketone of formula I (R1, R2 are H, alkyl, aryl; R2 is alkyl, aryl; R4 is alkyl, aralkyl; R5 is H, alkyl, cycloalkyl, aralkyl) is treated with a base in a solvent selected from an aprotic polar solvent, an ether solvent and an aromatic solvent to obtain a diaziridine ketone of formula II. The β-alkoxyaminoketone of formula I is obtained by reacting an α,β-unsaturated ketone of formula III with an O-alkylhydroxylamine of formula IV or its salt. The O-alkyl hydroxylamine of formula IV includes O- methylhydroxylamine. The solvent includes N,N-dimethylformamide, terahydrofuran and benzene.