反应详情

To a stirred solution of potassium hydroxide (4.83 g, 75 mmol) in water (4.2 mL) and ethanol (15 mL) was added 2,2-bis(6-hydroxy-5,5-dimethylhexyl)malonic acid diethyl ester (15.0 g). The reaction mixture was heated at reflux for 14 h. The ethanol was removed under reduced pressure and the aqueous solution was extracted with chloroform (2×50 mL). The aqueous layer was acidified with hydrochloric acid to pH 1 and extracted with diethyl ether (3×50 mL). The ethereal phases were dried over magnesium sulfate and concentrated in vacuo to yield 2,2-bis(6-hydroxy-5,5-dimethylhexyl)malonic acid (7.8 g, 82%) as a yellow solid. M.P.: 178-180° C. 1H NMR (300 MHz, CD3OD/TMS): δ (ppm): 4.86 (s br., 4H), 3.22 (s, 4H), 1.9-1.8 (m, 4H), 1.36-1.10 (m, 12H), 0.84 (s, 12H). 13C NMR (75 MHz, CD3OD/TMS): δ (ppm): 176.0, 72.0, 58.7, 39.8, 36.0, 34.1, 26.5, 25.5, 24.5. HRMS (LSIMS, gly): Calcd. for C19H37O6 (MH+): 361.2590. found: 361.2582.

1. temperatureThe reaction mixture was heated
2. temperatureat reflux for 14 h
3. customThe ethanol was removed under reduced pressure
4. extractionthe aqueous solution was extracted with chloroform (2×50 mL)
5. extractionextracted with diethyl ether (3×50 mL)
6. dry with materialThe ethereal phases were dried over magnesium sulfate
7. concentrationconcentrated in vacuo