反应详情

Sodium hydroxide (4.75 g, 119 mmol) was added to a solution of (4-cyclopentyloxy-3-methoxy-phenyl)-acetic acid methyl ester (12.4, 46.9 mmol) in methanol) 100 ml)/water (100 ml) and the reaction was stirred at room temperature for 3.5 hours. The methanol was removed under reduced pressure and the aqueous phase was washed with diethylether (100 ml) then acidified to pH 2 using concentrated hydrochloric acid. This was then extracted with ethyl acetate (2×200 ml) and the combined organic extracts were washed with brine (100 ml), dried over Na2SO4 and concentrated under reduced pressure to give (4-cyclopentyloxy-3-methoxy-phenyl)-acetic acid (11.1 g) as a white solid. 1H NMR (400 MHz, CD3OD): δ=6.87 (1H, s), 6.81-6.86 (1H, d), 6.76-6.80 (1H, d), 4.75-4.79 (1H, brs), 3.78 (3H, s), 3.49 (2H, s), 1.71-1.89 (6H, m), 1.56-1.64 (2H, m) ppm. LRMS (electrospray): m/z [M−H]+ 249, [2M−H]+ 499. Anal. Found C, 67.15; H, 7.25. C14H18O4 requires C, 67.18; H, 7.25%.

1. customThe methanol was removed under reduced pressure
2. washthe aqueous phase was washed with diethylether (100 ml)
3. extractionThis was then extracted with ethyl acetate (2×200 ml)
4. washthe combined organic extracts were washed with brine (100 ml)
5. dry with materialdried over Na2SO4
6. concentrationconcentrated under reduced pressure