反应详情

The crude methyl 2-(2'-benzyloxyphenyl)-3-hydroxyacrylate was dissolved in dry DMF (100 ml) and potassium carbonate (29.0 g) was added in one portion. Dimethyl sulphate (16.00 g) in dry DMF (10 ml) was then added dropwise with stirring. After ninety minutes, water (300 ml) was added and the solution was extracted with ether (2×300 ml). After washing with water (3×150 ml) and brine, the extracts were dried and concentrated under reduced pressure, and the resulting yellow oil solidified on trituration with ether/petrol. Recrystallization from dry methanol afforded (E)-methyl 2-(2'-benzyloxyphenyl)-3-methoxyacrylate as a white, crystalline solid (5.44 g, 17% yield from methyl 2-benzyloxyphenylacetate), mp. 76°-77° C.; infrared max. (nujol mull): 1710, 1640 cm-1 ; 1H nmr (90 MHz): delta 3.63 (3H,s), 3.75 (3H,s), 5.05 (2H,s), 6.80-7.40 (9H,m), 7.50 (1H,s)ppm.

1. waitAfter ninety minutes
2. extractionthe solution was extracted with ether (2×300 ml)
3. washAfter washing with water (3×150 ml) and brine
4. customthe extracts were dried
5. concentrationconcentrated under reduced pressure
6. customRecrystallization from dry methanol