反应详情

温度

-78 °C

Diisopropyl amine (5.04 ml, 36.02 millimole) and dry tetrahydrofuran (30 ml) were introduced into a reaction vessel sufficiently substituted by argon gas. The reaction mixture was cooled to -78° C., and then 1.6M butyl lithium/hexane solution (23.64 ml, 37.82 millimole) was added dropwise thereto. The cooling bath was removed and the solution was allowed to warm to 0° C. and stirred for 30 minutes at the same temperature. The lithium diisopropylamide/tetrahydrofuran solution was again cooled to -78° C., and palmitic acid (4.62 g, 18.02 millimole) in dry tetrahydrofuran (60 ml) was added thereto, and the reaction mixture was stirred for 15 minutes at the same temperature (-78° C.). Then, the reaction temperature was raised to room temperature, and the reaction was continued for 1 hour. The reaction mixture was again cooled to -78° C., and 9-octadecenal (4 g, 15.02 millimole) in dry tetrahydrofuran (60 ml) was added dropwise thereto. The obtained mixture was reacted for 4 hours under the same conditions, and allowed to warm to 0° C., and the reaction was stopped by adding 1N hydrochloric acid (200 ml). The reaction mixture was extracted thrice with chloroform. The organic phase was washed twice with water and then dried over anhydrous sodium sulfate. The inorganic salt was filtered off and the solvent was distilled off from the filtrate. The obtained residue was dissolved in a developing solvent and fractionated through silicagel chromatography (n-hexane:ethyl acetate=8:2→chloroform:methanol=95:5) to give 3-hydroxy-2-n-tetradecyl-11-icosenoic acid (II)(3.73 g, yield 47.5%) in the form of white viscous solid.

1. customThe cooling bath was removed
2. temperatureto warm to 0° C.
3. temperatureThe lithium diisopropylamide/tetrahydrofuran solution was again cooled to -78° C.
4. stirringthe reaction mixture was stirred for 15 minutes at the same temperature (-78° C.)
5. temperatureThen, the reaction temperature was raised to room temperature
6. waitthe reaction was continued for 1 hour
7. temperatureThe reaction mixture was again cooled to -78° C.
8. customThe obtained mixture was reacted for 4 hours under the same conditions
9. temperatureto warm to 0° C.
10. extractionThe reaction mixture was extracted thrice with chloroform
11. washThe organic phase was washed twice with water
12. dry with materialdried over anhydrous sodium sulfate
13. filtrationThe inorganic salt was filtered off
14. distillationthe solvent was distilled off from the filtrate
15. dissolutionThe obtained residue was dissolved in a developing solvent