反应详情

8.6 ml (76.08 mmol) of (R)-(−)-2,2-dimethyl-1,3-dioxolane-4-methanol, 15 grams of powdered potassium hydroxide and 27.5 grams (76.08 mmol) of 1-bromoeicosane were stirred in 150 ml benzene and refluxed for 6 hours, while removing the water formed by azeotropic distillation. The volume of the solvent was gradually reduced to about 70 ml. The reaction mixture was then cooled to room temperature and 150 ml of water was added. The reaction mixture was then extracted thrice with 150 ml diethyl ether, the combined organic phase was washed with 100 ml water, and the solvent was then removed under reduced pressure. The obtained residue was dissolved in 105 ml of a 90:10:5 (v/v) methanol:water:concentrated hydrochloric acid mixture, and the resulting solution was refluxed until the solution became clear. The solution was then cooled to room temperature and 100 ml water was added. The product was extracted with 150 ml chloroform, washed consecutively with 150 ml water, 150 ml saturated aqueous solution of sodium carbonate, and again with 150 ml water. The solvent was then removed under reduced pressure and the product was crystallized from 200 ml hexane, yielding 21.0 grams of pure 1-eicosanyl-sn-glycerol, which was dried in a desiccator under reduced pressure with phosphorus oxide. The yield was 81.5%.

1. temperaturerefluxed for 6 hours
2. customwhile removing the water
3. customformed by azeotropic distillation
4. extractionThe reaction mixture was then extracted thrice with 150 ml diethyl ether
5. washthe combined organic phase was washed with 100 ml water
6. customthe solvent was then removed under reduced pressure
7. dissolutionThe obtained residue was dissolved in 105 ml of a 90:10:5 (v/v) methanol
8. temperaturewater:concentrated hydrochloric acid mixture, and the resulting solution was refluxed until the solution
9. temperatureThe solution was then cooled to room temperature
10. addition100 ml water was added
11. extractionThe product was extracted with 150 ml chloroform
12. washwashed consecutively with 150 ml water, 150 ml saturated aqueous solution of sodium carbonate
13. customThe solvent was then removed under reduced pressure
14. customthe product was crystallized from 200 ml hexane