反应详情

To a solution of (Z)-2-ethoxy-3-[2-methyl-4-(5-methyl-2-o-tolyl-oxazol-4-ylmethoxy)-phenyl]-acrylic acid ethyl ester (6.8 g, 15.6 mmol) in THF/methanol 2/1 (102 ml) was added a 3 M aqueous NaOH solution (26 ml, 78 mmol). The reaction mixture was stirred for 3 h at ambient temperature, concentrated under reduced pressure, diluted with ice water and acidified with with 1 M aqueous HCl solution. Twofold extraction with ethyl acetate was followed by washing of the combined extracts with ice water/brine 1/1 (three times) and drying of the organic layer over sodium sulfate. The solvent was removed under reduced pressure and the crude product crystallized from dichloromethane/n-heptane to give the title compound (6.3 g, 15.5 mmol, 99%) as colorless crystals.

1. concentrationconcentrated under reduced pressure
2. additiondiluted with ice water
3. extractionTwofold extraction with ethyl acetate
4. washby washing of the combined extracts with ice water/brine 1/1 (three times)
5. dry with materialdrying of the organic layer over sodium sulfate
6. customThe solvent was removed under reduced pressure
7. customthe crude product crystallized from dichloromethane/n-heptane