反应详情

A mixture of 11.2 g (50 mmol) of 4-benzyloxy-2-methyl-benzaldehyde [PCT Int. Appl. (2002), WO 2002/092084/A1] and of 12.33 g (55 mmol) of triethyl phosphonoacetate in 25 ml of absolute ethanol was added to a cooled solution (0° C.) of sodium ethylate (freshly prepared from 1.38 g (60 mmol) of sodium and 25 ml of absolute ethanol). Subsequently, the mixture was stirred at ambient temperature for 2 hours. Then, the solvent was evaporated and the residue was partioned between tert.-butyl methyl ether and water. The organic layer was washed with brine, dried over anhydrous sodium sulfate and finally evaporated. After crystallization from a mixture of dichloromethane and n-heptane, 12.9 g of (E)-3-(4-benzyloxy-2-methyl-phenyl)-acrylic acid ethyl ester was obtained as beige crystals (87% of theory).

1. customThen, the solvent was evaporated
2. washThe organic layer was washed with brine
3. dry with materialdried over anhydrous sodium sulfate
4. customfinally evaporated
5. customAfter crystallization
6. additionfrom a mixture of dichloromethane and n-heptane