反应详情

温度

70 °C

To a solution of methyl 4-(2-hydroxyethoxy)-3-methyl-benzoate (1.87 g, 8.9 mmol) in dioxane (16 mL) was added 1N NaOH (5 mL) and the reaction mixture was heated at 70° C. for 18 hours. 5M NaOH (0.5 ml) was added and the reaction was stirred at 70° C. for 22 hours. The reaction mixture was cooled and solvent was concentrated in vacuo and the crude residue was dissolved in water (20 mL) and extracted with ethyl acetate (2×20 mL). The aqueous layer was acidified with 1 M HCl solution and extracted with ethyl acetate (2×20 mL). The organics were separated, dried with Na2SO4 and concentrated in vacuo to give 4-(2-hydroxyethoxy)-3-methyl-benzoic acid (0.77 g, 44%) as a white solid. ESI-MS m/z calc. 196.1. Found 197.0 (M+1)+; Retention time: 0.72 minutes (3 min run). 1H NMR (400 MHz, DMSO) δ 12.51 (s, 1H), 7.96-7.49 (m, 2H), 7.00 (d, J=8.6 Hz, 1H), 4.87 (t, J=5.4 Hz, 1H), 4.06 (t, J=5.0 Hz, 2H), 3.75 (q, J=5.1 Hz, 2H), 2.17 (d, J=20.3 Hz, 3H).

1. temperatureThe reaction mixture was cooled
2. concentrationsolvent was concentrated in vacuo
3. dissolutionthe crude residue was dissolved in water (20 mL)
4. extractionextracted with ethyl acetate (2×20 mL)
5. extractionextracted with ethyl acetate (2×20 mL)
6. customThe organics were separated
7. dry with materialdried with Na2SO4
8. concentrationconcentrated in vacuo