反应详情

To a homogeneous solution of potassium hydroxide (1.18 g, 21 mmol) in water (1.12 mL) and ethanol (3.8 mL) was added 7-hydroxymethyl-2,2,12,12-tetramethyltridecanedioic acid diethyl ester (2.9 g, 7.5 mmol) and the reaction mixture was heated at reflux for 4 h. The mixture was concentrated in vacuo, cooled to room temperature, and the residue was extracted with diethyl ether (2×50 mL). The pH of the aqueous layer was adjusted to 1 by addition of hydrochloric acid. The product was extracted with diethyl ether (3×50 mL). The combined organic layers were dried over sodium sulfate and concentrated in vacuo to afford the crude product which was purified by column chromatography on silica (hexanes:ethyl acetate=60:40) to yield 7-hydroxymethyl-2,2,12,12-tetramethyltridecanedioic acid (2.0 g, 81%) as an oil. 1H NMR (300 MHz, CDCl3/TMS): δ (ppm): 7.64 (br., 3H), 3.50 (d, 2H, J=4.4 Hz), 1.60-1.20 (m, 17H), 1.16 (s, 12H). 13C NMR (75 MHz, CDCl3/TMS): δ (ppm): 184.3, 65.2, 42.1, 40.5, 40.1, 30.6, 27.1, 25.2, 25.0. HRMS (LSIMS, nba): Calcd. for C18H35O5 (MH+): 331.2484. found 331.2484.

1. temperaturethe reaction mixture was heated
2. temperatureat reflux for 4 h
3. concentrationThe mixture was concentrated in vacuo
4. extractionthe residue was extracted with diethyl ether (2×50 mL)
5. additionThe pH of the aqueous layer was adjusted to 1 by addition of hydrochloric acid
6. extractionThe product was extracted with diethyl ether (3×50 mL)
7. dry with materialThe combined organic layers were dried over sodium sulfate
8. concentrationconcentrated in vacuo
9. customto afford the crude product which
10. customwas purified by column chromatography on silica (hexanes:ethyl acetate=60:40)