Реакция #1552097

Уравнение реакции

benzene

(R)-(−)-2,2 dimethyl-1,3-dioxolane-4-methanol

potassium hydroxide

hexadecyl bromide

→

1-hexadecyl-glycerol

Выход 79.0%

Растворители

water

Условия реакции

Обработка

1. 1
   Температураrefluxed for 6 hours
2. 2
   Другоеwhile removing the water
3. 3
   Другоеformed by azeotropic distillation
4. 4
   workup.STIRRINGstirred at this temperature overnight
5. 5
   Экстракцияthe obtained mixture was extracted thrice with 150 ml diethyl ether
6. 6
   ПромывкаThe combined organic phase was washed with 150 ml water
7. 7
   Другоеthe solvent was then removed under reduced pressure
8. 8
   workup.DISSOLUTIONThe residue was dissolved in 200 ml of a mixture of 90:10:5 (volume/volume) methanol
9. 9
   Температураwater:concentrated HCl, and the resulting solution was refluxed for 2 hours
10. 10
    ТемператураAfter cooling to room temperature
11. 11
    workup.ADDITIONadding 200 ml water
12. 12
    Экстракцияthe product was extracted with 250 ml chloroform
13. 13
    ПромывкаThe organic phase was washed consecutively with 250 ml water, 200 ml saturated aqueous solution of sodium carbonate
14. 14
    ДругоеThe solvent was removed under reduced pressure
15. 15
    Другоеthe product was then crystallized from hexane (500 ml)

Методика

A mixture of 40 ml (R)-(−)-2,2 dimethyl-1,3-dioxolane-4-methanol, 55 grams of powdered potassium hydroxide and 109 ml hexadecyl bromide were added to 500 ml benzene, and the reaction mixture was stirred and refluxed for 6 hours, while removing the water formed by azeotropic distillation. The volume of the solvent was gradually reduced to about 150 ml. The reaction mixture was then cooled to room temperature and stirred at this temperature overnight. Thereafter, 150 ml water was added, and the obtained mixture was extracted thrice with 150 ml diethyl ether. The combined organic phase was washed with 150 ml water and the solvent was then removed under reduced pressure. The residue was dissolved in 200 ml of a mixture of 90:10:5 (volume/volume) methanol:water:concentrated HCl, and the resulting solution was refluxed for 2 hours. After cooling to room temperature and adding 200 ml water, the product was extracted with 250 ml chloroform. The organic phase was washed consecutively with 250 ml water, 200 ml saturated aqueous solution of sodium carbonate, and again with 200 ml water. The solvent was removed under reduced pressure and the product was then crystallized from hexane (500 ml) to give 81.25 grams (yield 79%) of pure 1-hexadecyl-glycerol, which was dried in a desiccator under reduced pressure.

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