反应详情

温度

85 °C

Compound 1-3a was added to a solution of aqueous 2 N NaOH. The suspension was stirred at 80-90° C. until the reaction mixture became clear and was then held at reflux for 1-2 h. The solution was cooled and acidified with aqueous 3 N HCl, then the resulting precipitate was collected by filtration, washed with water, and dried under vacuum over P2O5 to provide the product (1-4a) in 99% yield. 1H NMR (CDCl3-d, 300 MHz) δ (ppm) 5.31 (s, 2H), 7.06-7.18 (m, 3H), 7.30-7.42 (m, 3H), 7.47-7.50 (m, 2H), 11.93 (bs, 1H).

1. temperatureat reflux for 1-2 h
2. temperatureThe solution was cooled
3. filtrationthe resulting precipitate was collected by filtration
4. washwashed with water
5. dry with materialdried under vacuum over P2O5