反应详情

A solution of 2,2-bis[5,5-dimethyl-6-(tetrahydropyran-2-yloxy)-hexyl]malonic acid diethyl ester (2.92 g, 5.0 mmol) in concentrated hydrochloric acid (2.4 mL) and water (1.6 mL) was heated at reflux for 1 h. Ethanol (8.2 mL) was added and the reaction mixture was heated at reflux for 3 h. The reaction mixture was diluted with water (20 mL) and extracted with diethyl ether (3×20 mL). The combined organic layers were washed with water (20 mL) and brine (20 mL), dried over sodium sulfate, and concentrated in vacuo to afford 2,2-bis(6-hydroxy-5,5-dimethylhexyl)malonic acid diethyl ester (1.74 g, 84%) as an oil. 1H NMR (300 MHz, CDCl3/TMS): δ (ppm): 4.13 (q, 4H, J=7.2 Hz), 3.25 (s, 4H), 2.42 (s, 2H), 1.90-1.75 (m, 4H), 1.30-1.12 (m, 18H), 0.84 (s, 12H). 13C NMR (75 MHz, CDCl3/TMS): δ (ppm): 172.0, 71.7, 60.9, 57.4, 38.2, 34.9, 32.1, 24.8, 24.0, 23.7, 14.0. HRMS (LSIMS, gly): Calcd. for C23H45O6 (MH+): 417.3216. found: 417.3210.

1. temperatureat reflux for 1 h
2. temperaturethe reaction mixture was heated
3. temperatureat reflux for 3 h
4. extractionextracted with diethyl ether (3×20 mL)
5. washThe combined organic layers were washed with water (20 mL) and brine (20 mL)
6. dry with materialdried over sodium sulfate
7. concentrationconcentrated in vacuo