Реакция #2175467

Уравнение реакции

NaHCO3

hydrochloride salt

(2R)-2-Phenylcarbonyloxypropyl (2S)-2-amino-3-(3,4-dihydroxyphenyl)propanoate hydrochloride

Methanesulfonic acid

ethyl acetate

methanesulfonic acid

→

mesylate salt

Выход 99.3%

(2R)-2-Phenylcarbonyloxypropyl (2S)-2-amino-3-(3,4-dihydroxyphenyl)propanoate mesylate

Выход 99.3%

Растворители

water

water

Условия реакции

Обработка

1. 1
   ЭкстракцияThe resulting aqueous suspension was extracted with ethyl acetate (EtOAc) (2×400 mL)
2. 2
   ЭкстракцияThe combined EtOAc extract
3. 3
   Промывкаwas washed with water
4. 4
   Сушкаbrine, and dried through MgSO4
5. 5
   ДругоеWhite precipitate
6. 6
   Другоеformed as
7. 7
   workup.STIRRINGThe suspension was stirred for another 30 min
8. 8
   Фильтрацияfiltered
9. 9
   ПромывкаThe filter cake was washed three times with ethyl acetate (EtOAc) and vacuum
10. 10
    Другоеdried overnight

Методика

A solution of NaHCO3 (9.87 g, 117.5 mmol) in water (80 mL) was slowly added to a solution of hydrochloride salt 1d (31.0 g, 78.3 mmol) in water (300 mL). The resulting aqueous suspension was extracted with ethyl acetate (EtOAc) (2×400 mL). The combined EtOAc extract was washed with water, then brine, and dried through MgSO4. Methanesulfonic acid (6.04 mL, 93.12 mmol) was slowly added to the ethyl acetate (EtOAc) solution while stirred. White precipitate formed as soon as the addition of methanesulfonic acid was complete. The suspension was stirred for another 30 min and then filtered. The filter cake was washed three times with ethyl acetate (EtOAc) and vacuum dried overnight to afford 35.4 g (quantitative yield) of anhydrous mesylate salt 1 as a white solid. 1H NMR (400 MHz, CD3OD): δ 1.40 (d, J=6.4 Hz, 3H), 2.70 (s, 3H), 2.98 (dd, J=7.8, 14.6 Hz, 1H), 3.10 (dd, J=5.6, 14.4 Hz, 1H), 4.24 (dd, J=5.8, 7.8 Hz, 1H), 4.38 (dd, J=6.8, 12.0 Hz, 1H), 4.52 (dd, J=3.4, 11.8 Hz, 1H), 5.40 (dp, J=3.2, 6.4 Hz, 1H), 6.52 (dd, J=2.2, 8.2 Hz, 1H), 6.67 (d, J=2.2 Hz, 1H), 6.69 (d, J=8.0 Hz, 1H), 7.47 (t, J=7.6 Hz, 2H), 7.60 (br t, J=7.4 Hz, 1H), 8.01 (d, J=7.6 Hz, 2H). MS (ESI) m/z 360.07 (M+H)+ and 358.01 (M−H)−.

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