反应详情

A mixture of 5-acetyl-2-ethoxybenzoic acid methyl ester (9.6 g, 0.043 mol), 5M aqueous sodium hydroxide solution (44 ml, 0.217 mol), water (80 ml) and 1,4-dioxan (80 ml) was stirred at room temperature for 18 hours. The solvent was removed by evaporation under vacuum, the residue dissolved in water (100 ml) and the resulting solution acidified to pH 1 with concentrated hydrochloric acid. The aqueous mixture was extracted with ethyl acetate (4×100 ml) and the combined extracts dried (Na2SO4) and evaporated under vacuum. The resulting solid was crystallised from ethyl acetate to give the title compound as a colourless solid (5.4 g, 60%), m.p. 122°-135° C. Found: C,63.20; H,5.81. C11H12O4 requires C,63.45; H,5.81%.

1. customThe solvent was removed by evaporation under vacuum
2. dissolutionthe residue dissolved in water (100 ml)
3. extractionThe aqueous mixture was extracted with ethyl acetate (4×100 ml)
4. dry with materialthe combined extracts dried (Na2SO4)
5. customevaporated under vacuum
6. customThe resulting solid was crystallised from ethyl acetate