反应详情

Ester 6a (0.75 g, 2.5 mmol) was dissolved in 10 ml of 1N NaOH. After being kept at room temperature for 30 min the solution was acidified with 1N HCl to pH of 3. The precipitated material was collected by filtration and washed with water. Drying under vacuum over P2O5 afforded 0.705 g of acid 7a as an off-white solid. 1H NMR (DMSO-d6): δ 12.2 (br s, 1H), 10.41 (br s, 1H), 7.50 (s, 1H), 6.23 (s, 1H), 2.89 (t, J=7.5 Hz, 2H), 2.53 (t, J=7.5 Hz, 2H), 2.38 (s, 3H).

1. filtrationThe precipitated material was collected by filtration
2. washwashed with water
3. dry with materialDrying under vacuum over P2O5