반응 #1244292

반응 방정식

Ethyl 4-chloroacetoacetate

glucose

NaOH

NADP

→

ethyl (S)-4-chloro-3-hydroxybutyrate

수율 87.4%

용매

Butyl acetate

water

반응 조건

후처리

1. 1
   workup.ADDITIONTo a 100 mL vessel connected to an automatic titrater by a pH electrode and a feeding tube for addition of base
2. 2
   workup.ADDITIONTo this solution was charged ketoreductase SEQ ID NO
3. 3
   workup.ADDITION1 mL was charged rapidly
4. 4
   workup.ADDITIONthe remainder was then charged at a rate of 1 mL/hr)
5. 5
   기타to separate
6. 6
   기타was separated
7. 7
   세척washed with 10 mL of water
8. 8
   추출The combined aqueous layers were extracted twice with 20 mL of butyl acetate
9. 9
   기타rotary evaporated under vacuum
10. 10
    기타to remove water
11. 11
    workup.ADDITIONAdditional butyl acetate was added during the evaporation
12. 12
    기타to help remove the water
13. 13
    기타When the water was removed the butyl acetate solution
14. 14
    기타was decanted from solids in the flask
15. 15
    기타Evaporation of the solvent under vacuum

실험 절차

To a 100 mL vessel connected to an automatic titrater by a pH electrode and a feeding tube for addition of base was charged a solution of glucose (12. g) in water (30 mL). To this solution was charged ketoreductase SEQ ID NO: 42 (100 mg); 50 mg GDH SEQ ID NO: 66 and NADP (6.25 mg). Butyl acetate (10 ml) was then charged. Ethyl 4-chloroacetoacetate (10 g) was then charged via syringe pump as follows: 1 mL was charged rapidly and the remainder was then charged at a rate of 1 mL/hr). The pH was maintained at 7 by the automatic titrater by the addition of 4M NaOH over 18 hours hrs. The stirring was stopped and the phases allowed to separate. The organic layer included some emulsion. The organic layer, including some emulsion, was separated and washed with 10 mL of water. The combined aqueous layers were extracted twice with 20 mL of butyl acetate. The organic extracts were combined and rotary evaporated under vacuum to remove water. Additional butyl acetate was added during the evaporation to help remove the water. When the water was removed the butyl acetate solution was decanted from solids in the flask. Evaporation of the solvent under vacuum then gave 8.85 g of ethyl (S)-4-chloro-3-hydroxybutyrate (87.4% yield) of very good purity.

출처