反应详情

温度

160 °C

3.0 g (10.5 mmol) of ethyl [2-cyano-1-(2,4-dichlorophenyl)ethenyl]carbamate (Example 128A) and 1.39 g (10.5 mmol) of ethyl hydrazino(oxo)acetate are dissolved in NMP (16 ml) and stirred in a flask with a calcium chloride drying tube at an oil-bath temperature of 160° C. for 4 h. The reaction mixture is cooled to RT and ethyl acetate (150 ml) and water (100 ml) are added. The organic phase is separated off, dried with magnesium sulphate and concentrated. The residue is chromatographed on silica gel (mobile phase cyclohexane/ethyl acetate 10:1 to 1:1, then with dichloromethane/methanol 100:1). The crude product is concentrated, mixed with water and stirred for 1 h. The solid is filtered off with suction and dried; 1.31 g (35% of theory) of the product are obtained.

1. temperatureThe reaction mixture is cooled to RT
2. customThe organic phase is separated off
3. dry with materialdried with magnesium sulphate
4. concentrationconcentrated
5. customThe residue is chromatographed on silica gel (mobile phase cyclohexane/ethyl acetate 10:1 to 1:1
6. concentrationThe crude product is concentrated
7. additionmixed with water
8. stirringstirred for 1 h
9. filtrationThe solid is filtered off with suction
10. customdried
11. custom1.31 g (35% of theory) of the product are obtained