반응 #806253

반응 방정식

ethyl 4-chloroacetoacetate

glucose

2

Glucose

potassium phosphate

NaCl

glucose

Na2CO3

NADP

→

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

수율 97.0%

용매

butyl acetate

butyl acetate

반응 조건

후처리

1. 1
   workup.ADDITIONTo this was added ketoreductase SEQ ID NO
2. 2
   workup.DISSOLUTIONOnce dissolved
3. 3
   기타to form an emulsion
4. 4
   온도The pH was maintained between 6.8 and 7 by an automatic titrater that
5. 5
   workup.ADDITIONAfter 40 hours the automated addition of the base
6. 6
   기타The layers were separated
7. 7
   세척the aqueous phase was washed with ethyl acetate (500 mL)
8. 8
   건조The combined organics were dried over anhydrous sodium sulfate
9. 9
   여과filtered
10. 10
    기타evaporated on a rotary evaporator

실험 절차

To a well-stirred solution of 100 mM potassium phosphate buffer, 500 mM NaCl, pH 7 (1 L) at room temperature was added glucose (160 g, 830 mmoles, 1.1 equiv). To this was added ketoreductase SEQ ID NO: 2 (0.9 g), glucose dehydrogenase S06 SEQ ID. NO: 10 (0.5 g) and NADP (0.5 g) as lyophilized powders. Once dissolved, butyl acetate (500 mL) was added to form an emulsion. To this emulsion was added a solution of ethyl 4-chloroacetoacetate (100 g, 608 mmoles) in butyl acetate (500 mL), dropwise over 3 hours. The pH was maintained between 6.8 and 7 by an automatic titrater that dispensed Na2CO3 (2M in water, about 160 mL total). After 40 hours the automated addition of the base had ceased and there was no residual starting material by gas chromatography. The layers were separated, and the aqueous phase was washed with ethyl acetate (500 mL). The combined organics were dried over anhydrous sodium sulfate, filtered and evaporated on a rotary evaporator, to give essentially pure (˜97%) ethyl (S)-4-chloro-3-hydroxybutyrate.

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