反应详情

A mixture of 3,5-dichlorobenzamide (19.0 g) and methyl glyoxylate (8.8 g) in ethyl acetate (300 ml) was heated under reflux for 8 hours. The solvent was removed and the residual adduct was crystallised from chloroform-light petroleum. A portion (4.0 g) of the adduct was dissolved in a mixture of glacial acetic acid (30 ml) and acetonitrile (10 ml) with stirring, and then concentrated sulphuric acid (4 ml) was added. The mixture was kept at room temperature overnight when water (100 ml) was added. The precipitated solid was washed with water, dried, and crystallised from ethanol to give the product (2.45 g) as a colourless crystalline solid, m.p. 235°-237°.

1. temperaturewas heated
2. temperatureunder reflux for 8 hours
3. customThe solvent was removed
4. customthe residual adduct was crystallised from chloroform-light petroleum
5. dissolutionA portion (4.0 g) of the adduct was dissolved in a mixture of glacial acetic acid (30 ml) and acetonitrile (10 ml)
6. additionconcentrated sulphuric acid (4 ml) was added
7. additionwhen water (100 ml) was added
8. washThe precipitated solid was washed with water
9. customdried
10. customcrystallised from ethanol