反应详情

To a solution of NaOH (20 g, 0.50 mol) in H2O (20 mL) was added 1-(3,4-dihydroxy-phenyl)-cyclopropanecarbonitrile (4.4 g, 25 mmol). The mixture was heated at reflux for 3 h before being cooled to room temperature. The mixture was neutralized with HCl (0.5 N) to pH 3-4 and extracted with ethyl acetate (20 mL×3). The combined organic layers were washed with water, brine, dried over anhydrous MgSO4, and concentrated under vacuum to obtain 1-(3,4-dihydroxy-phenyl)-cyclopropanecarboxylic acid (4.5 g crude). From 900 mg crude, 500 mg pure 1-(3,4-dihydroxy-phenyl)-cyclopropanecarboxylic acid was obtained by preparatory HPLC. 1H NMR (DMSO, 300 MHz) δ 12.09 (br s, 1H), 8.75 (br s, 2H), 6.50-6.67 (m, 3H), 1.35-1.31 (m, 2H), 1.01-0.97 (m, 2H).

1. temperatureThe mixture was heated
2. temperatureat reflux for 3 h
3. extractionextracted with ethyl acetate (20 mL×3)
4. washThe combined organic layers were washed with water, brine
5. dry with materialdried over anhydrous MgSO4
6. concentrationconcentrated under vacuum