تفاعل #86017

معادلة التفاعل

hydrochloric acid

ammonia

(R)-1-ethyl hydrogen 3-benzyloxycarbonylamino-3-ethoxycarbonylsuccinate

isobutyl chloroformate

→

title compound

المردود 84.0%

(R)-diethyl 2-benzyloxycarbonylamino-2-carbamoylsuccinate

المردود 84.0%

المذيبات

THF

triethylamine

ظروف التفاعل

المعالجة

1. 1
   workup.STIRRINGthe mixture was stirred for 5 minutes
2. 2
   workup.STIRRINGThe reaction mixture was stirred at the same temperature for 1 hour
3. 3
   استخلاصthe mixture was extracted with ethyl acetate
4. 4
   تجفيفthe extract was dried over anhydrous magnesium sulfate
5. 5
   أخرىThe solvent was evaporated under reduced pressure
6. 6
   غسيلthe residue was subjected to silica gel column chromatography, in which elution
7. 7
   أخرىwas performed with n-hexane/ethyl acetate (1:1) for purification
8. 8
   أخرىcrystallized from ethyl acetate/n-hexane

الإجراء التجريبي

A solution of (R)-1-ethyl hydrogen 3-benzyloxycarbonylamino-3-ethoxycarbonylsuccinate (1.8 g) in THF (20 mL) was added with triethylamine (0.96 mL) and isobutyl chloroformate (0.84 mL, 0.87 g) in this order at −15° C. with stirring, and the mixture was stirred for 5 minutes. A solution of 25% aqueous ammonia (0.47 mL) was dropped into the reaction mixture at the same temperature. The reaction mixture was stirred at the same temperature for 1 hour, and then poured into diluted hydrochloric acid, the mixture was extracted with ethyl acetate, and the extract was 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 crystallized from ethyl acetate/n-hexane to obtain the title compound (1.51 g, yield: 84%) as colorless crystals. Optical rotation [α]D25 was −5.7° (c 0.52, ethanol) and optical purity was 96.1% ee.

المصدر