反应详情

4-(3-Cyclopentyloxy-4-methoxyphenyl)-2-pyrrolidone-1-acetate (250 mg, 0.72 mmol) was treated with 8 ml of a 1M solution of potassium hydroxide in 95% methanol. After 10 hours, the reaction solution was acidified with 2NHCl to pH 3 and 30 ml of water was added and the resulting mixture was extracted with 60 ml of ethyl acetate twice. The organic layer was concentrated and chromatographed (methanol/dichloromethane 5:100) to give 242 mg (quantitative yield) of 4-(3-cyclopentyloxy-4-methoxyphenyl)-2-pyrrolidone-1-acetic acid: 1H NMR (300 MHz, CDCl3) δ 6.85-73 (m, 3H), 4.84-4.74 (m, 1H), 4.20 (d, J=12.0 Hz, 1H), 4.12 (d, J=12.0, 1H), 3.82 (s, 4H), 3.66-3.46 (m, 2H), 2.89 (dd, J=16.8, 8.7 Hz, 1H), 2.58 (dd, J=16.8, 8.4 Hz, 1H), 2.00-1.72 (b, 6H), 1.70-1.50 (b, 2H).

1. additionwas added
2. extractionthe resulting mixture was extracted with 60 ml of ethyl acetate twice
3. concentrationThe organic layer was concentrated
4. customchromatographed (methanol/dichloromethane 5:100)