Reaktion #558533

Reaktionsgleichung

potassium carbonate

(R)-diethyl 2-t-butyloxycarbonylamino-2-carbamoylsuccinate

hydrochloric acid

→

title compound

Ausbeute 88.5%

(R)-2-t-butyloxycarbonylamino-2-ethoxycarbonylsuccinimide

Ausbeute 88.5%

Lösungsmittel

water

acetone

Reaktionsbedingungen

Aufarbeitung

1. 1
   Extraktionthe mixture was extracted with ethyl acetate
2. 2
   WaschenThe extract was washed with saturated brine
3. 3
   Trocknendried over anhydrous magnesium sulfate
4. 4
   SonstigeThe solvent was evaporated under reduced pressure
5. 5
   Waschenthe residue was subjected to silica gel column chromatography, in which elution
6. 6
   Sonstigewas performed with n-hexane/ethyl acetate (1:1) for purification
7. 7
   Sonstigerecrystallized from ethyl acetate/n-hexane

Vorschrift

(R)-diethyl 2-t-butyloxycarbonylamino-2-carbamoylsuccinate (590 mg) obtained in Example 15 was dissolved in acetone (6 mL) and water (6 mL), the solution was added with potassium carbonate (295 mg), the mixture was stirred for 6 hours, 1 mol/L hydrochloric acid was poured to the mixture, and the mixture was extracted with ethyl acetate. The extract was washed with saturated brine, and then dried over anhydrous magnesium sulfate. The solvent was evaporated under reduced pressure, and the residue was subjected to silica gel column chromatography, in which elution was performed with n-hexane/ethyl acetate (1:1) for purification, and then recrystallized from ethyl acetate/n-hexane to obtain the title compound (450 mg, yield: 88%) as colorless crystals. Optical rotation [α]D25 was −39.1° (c 0.50, ethanol). 1H NMR (CDCl3) δ (ppm): 8.50 (1H, br), 5.99 (1H, br), 4.32 (2H, q, J=7.2 Hz), 3.16 (2H, m), 1.44 (9H, s), 1.30 (3H, t, J=7.2 Hz)

Quelle