反应详情

A solution of sodium salt of ethyl 2-hydroxyimino-2-cyanoacetate (41.0 g) in water (200 ml) is stirred under ice-cooling, and a solution of methyl chloroformate (23.6 g) in acetone (20 ml) is dropwise added thereto. The resulting mixture is adjusted to pH 6 to 7 with the addition of an aqueous solution of sodium hydrogencarbonate and stirred for 1 hour. The precipitates are collected by filtration, washed with water and dried to give ethyl 2-methoxycarbonyloxyimino-2-cyanoacetate (41.1 g) as crystals melting at 68° to 70°C which is identified with the compound obtained in Example 9 by IR absorption spectrum.

1. temperaturecooling
2. filtrationThe precipitates are collected by filtration
3. washwashed with water
4. customdried