反应详情

Freshly prepared aq. NaOH (10 M in H2O, 10.3 mmol) was added to a stirring, room temperature solution of 171 (0.3966 g, 2.05 mmol) in MeOH (5.1 mL, 0.4 M) under N2. The reaction was then heated to reflux for 20 minutes. A small amount of starting material remained. A large amount of undesired product along with only a small amount of desired product was observed by HPLC. The reaction was concentrated, redissolved in H2O, and extracted with EtOAc (1 mL). 10% aq. HCl was added dropwise to the aqueous layer until the pH=2. The white solid that precipitated from the reaction was filtered off and washed with cold H2O. The solid was dried under vacuum overnight to obtain 0.0076 g (11.6%) of 172. 1H (CD3OD, 400 MHz): δ 5.62 (1H, s), 2.77 (2H, t, J=5.6 Hz), 2.52 (2H, t, J=5.4 Hz), 1.78-1.66 (4H, m) ppm. 13C (CD3OD, 100 MHz): δ 164.87, 129.69, 122.48, 120.57, 118.42, 24.74, 24.69, 24.35, 22.94 ppm. DEPT (CD3OD, 100 MHz): CH2 carbons: 24.74, 24.69, 24.35, 22.94; CH carbons: 120.57 ppm. HPLC: 8.896 min.

1. temperatureThe reaction was then heated
2. temperatureto reflux for 20 minutes