反应 #1483152

反应方程式

hydrochloric acid

ammonia

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

isobutyl chloroformate

→

title compound

收率 84.0%

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

收率 84.0%

溶剂

THF

triethylamine

反应条件

后处理

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
   萃取the mixture was extracted with ethyl acetate
4. 4
   干燥the extract was dried over anhydrous magnesium sulfate
5. 5
   其他The solvent was evaporated under reduced pressure
6. 6
   洗涤the residue was subjected to silica gel column chromatography, in which elution
7. 7
   其他was performed with n-hexane/ethyl acetate (1:1) for purification
8. 8
   其他crystallized from ethyl acetate/n-hexane

实验过程

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.

来源