反应详情

A mixture of 2′-methoxyacetophenone (50 mmol), ethyl cyanoacetate (50 mmol), acetic acid (1.14 mL) ammonium acetate (400 mg), and benzene (50 mL) is heated to reflux in a Dean-Stark apparatus. After approximately 10 hours, additional ethyl cyanoacetate (50 mmol), acetic acid (1.14 mL), and ammonium acetate (400 mg) are added. After an additional 10 hours, the reaction is cooled to room temperature, diluted with ethyl acetate (30 mL), washed with water (240 mL), brine (40 mL), and dried (Na2SO4). After filtering, the extract is concentrated in vacuo and the desired product, as a mixture of E and Z-isomers, is isolated by column chromatography on silica gel, eluting with 5% ethyl acetate in petroleum ether.

1. temperatureis heated
2. temperatureto reflux in a Dean-Stark apparatus
3. waitAfter an additional 10 hours
4. washwashed with water (240 mL), brine (40 mL)
5. dry with materialdried (Na2SO4)
6. filtrationAfter filtering
7. concentrationthe extract is concentrated in vacuo
8. additionthe desired product, as a mixture of E and Z-isomers
9. customis isolated by column chromatography on silica gel
10. washeluting with 5% ethyl acetate in petroleum ether