反应详情

温度

0 °C

L-2-Amino-4-pentenoic acid was added to a solution of 3.18 ml (43.5 mmol) of thionyl chloride in methanol (40 ml) which had been cooled to 0° C., and the mixture was stirred at room temperature for 24 hr. The reaction solution was concentrated under the reduced pressure and was then dried. A solution of this crude product thus obtained in diethyl ether (26 ml) was cooled to 0° C., and a saturated aqueous sodium hydrogencarbonate solution (26 ml) was added thereto. 2-Nitrobenzenesulfonyl chloride (4.24 g, 19.14 mmol) was added thereto, and the mixture was stirred at room temperature for 7 hr. Thereafter, the reaction solution was cooled to 0° C., N,N-dimethylethylenediamine (2 ml) was added thereto, and the mixture was stirred at room temperature for 30 min. The organic layer was separated. The aqueous layer was adjusted to pH 3 by the addition of citric acid and was extracted with diethyl ether. The combined organic layer was washed with a 3% aqueous citric acid solution, a saturated aqueous sodium hydrogencarbonate solution, and saturated brine in that order, was dried over anhydrous sodium sulfate and was then filtered. The filtrate was concentrated under the reduced pressure, and the residue was then purified by column chromatography on silica gel (hexane:ethyl acetate=5:1) to give 4.52 g (yield 83%) of the title compound.

1. concentrationThe reaction solution was concentrated under the reduced pressure
2. customwas then dried
3. customA solution of this crude product thus obtained in diethyl ether (26 ml)
4. temperaturewas cooled to 0° C.
5. stirringthe mixture was stirred at room temperature for 7 hr
6. temperatureThereafter, the reaction solution was cooled to 0° C.
7. stirringthe mixture was stirred at room temperature for 30 min
8. customThe organic layer was separated
9. additionThe aqueous layer was adjusted to pH 3 by the addition of citric acid
10. extractionwas extracted with diethyl ether
11. washThe combined organic layer was washed with a 3% aqueous citric acid solution
12. dry with materiala saturated aqueous sodium hydrogencarbonate solution, and saturated brine in that order, was dried over anhydrous sodium sulfate
13. filtrationwas then filtered
14. concentrationThe filtrate was concentrated under the reduced pressure
15. customthe residue was then purified by column chromatography on silica gel (hexane:ethyl acetate=5:1)