反应详情

According to the method described in J. Heterocyclic Chem., 24, 351 (1987), a mixture of 2-ethyl-3-oxobutanal, sodium salt (37.5 g, 0.275 mmol), cyanoacetamide (25.2 g, 0.30 mol), aqueous piperidinium acetate (22 mL) [prepared from glacial acetic acid (4.2 mL), water (10 mL) and piperidine (7.2 mL)] in water (775 ml) was refluxed for four hours. Glacial acetic acid (30 ml) was added cautiously (much foaming) as the product precipitated. Upon cooling to room temperature, the product was collected by filtration, washed with cold water and air dried to yield 22.3 g (50%), m.p. 237°-240° C.

1. temperaturewas refluxed for four hours
2. customprecipitated
3. filtrationthe product was collected by filtration
4. washwashed with cold water and air
5. customdried
6. customto yield 22.3 g (50%), m.p. 237°-240° C.