반응 #7381

반응 방정식

Thionyl chloride

D-glutamic acid

potassium hydrogen carbonate

benzyl chloroformate

ethyl acetate

→

title compound

Dimethyl (2R)-2-{[(benzyloxy)carbonyl]amino}pentanedioate

용매

methanol

water

반응 조건

후처리

1. 1
   온도the mixture subsequently heated
2. 2
   온도under reflux for 16 h
3. 3
   온도On cooling
4. 4
   농축the mixture was concentrated under reduced pressure
5. 5
   기타the residue azeotroped with toluene
6. 6
   기타to give a white solid
7. 7
   workup.ADDITIONwas added
8. 8
   세척The separated organic phase was washed with water
9. 9
   건조dried (over magnesium sulphate)
10. 10
    농축concentrated under reduced pressure
11. 11
    기타to provide a yellow oil
12. 12
    기타This oil was purified
13. 13
    세척flash column chromatography (silica, eluting with cyclohexane:ethyl acetate 2:1)

실험 절차

Thionyl chloride (30 ml) was added to a cooled solution of D-glutamic acid (33.2 g) in methanol (250 ml) and the mixture subsequently heated under reflux for 16 h. On cooling, the mixture was concentrated under reduced pressure and the residue azeotroped with toluene to give a white solid. This was stirred with ethyl acetate, water and potassium hydrogen carbonate at 0° C. while benzyl chloroformate (30 ml) was added. The mixture was warmed to room temperature and stirred for 5 h. The separated organic phase was washed with water, dried (over magnesium sulphate) and concentrated under reduced pressure to provide a yellow oil. This oil was purified using flash column chromatography (silica, eluting with cyclohexane:ethyl acetate 2:1) to give the title compound (22.45 g) as an oil.

출처