[OH:1][N:2]=[C:3]([C:9]([O:11][CH2:12][CH3:13])=[O:10])[C:4]([O:6][CH2:7][CH3:8])=[O:5].O.Cl[C:16]([O:18][CH2:19][CH3:20])=[O:17].C(=O)([O-])O.[Na+]>CC(C)=O>[CH2:19]([O:18][C:16]([O:1][N:2]=[C:3]([C:9]([O:11][CH2:12][CH3:13])=[O:10])[C:4]([O:6][CH2:7][CH3:8])=[O:5])=[O:17])[CH3:20]A mixture of diethyl 2-hydroxyiminomalonate (18.9 g), water (50 ml) and acetone (8 ml) is cooled at 0°C, and ethyl chloroformate (9.8 g) is dropwise added thereto. The resulting mixture is, after adjusted to pH 7 to 8 with the addition of an aqueous solution of sodium hydrogencarbonate, stirred at room temperature for 4 hours. The reaction mixture is extracted with ether, and the ether layer is washed with an aqueous solution of sodium chloride, dried and concentrated to give diethyl 2-ethoxycarbonyloxyiminomalonate (24 g) as an oil.
Loading…
