反应详情

To a solution of 3-isopropoxy-5-(2-thiophene-3-yl-ethoxy)-benzoic acid methyl ester (9.5 mmol) in a mixture of THF/MeOH 1/1 (40 ml) is added at 0° C. NaOH 1N (28.6 ml). Then the reaction mixture is stirred at room temperature for 6 h and the solvents are concentrated in vacuo. The residue is diluted with water (100 ml), the aqueous phase is extracted with ethyl ether (2×50 ml), acidified to pH 3 with conc. HCl and extracted with ethyl acetate (2×100 ml). The combined organic layer is washed with brine (50 ml), dried over MgSO4 and the solvent removed in vacuo. The residue is triturated with ethyl ether and pentane then filtered. 3-Isopropoxy-5-(2-thiophene-3-yl-ethoxy)-benzoic acid is obtained as white powder in a yield of 90%; MS: 307.1 (M+H+);

1. additionis added at 0° C
2. concentrationthe solvents are concentrated in vacuo
3. additionThe residue is diluted with water (100 ml)
4. extractionthe aqueous phase is extracted with ethyl ether (2×50 ml)
5. extractionextracted with ethyl acetate (2×100 ml)
6. washThe combined organic layer is washed with brine (50 ml)
7. dry with materialdried over MgSO4
8. customthe solvent removed in vacuo
9. customThe residue is triturated with ethyl ether and pentane
10. filtrationthen filtered