반응 #978020

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(S)-6-benzoyloxy-3-oxo-5-hydroxyhexanoic acid tert-butylester

(S)-6-benzoyloxy-3-oxo-5-hydroxyhexanoic acid tert-butylester

Hydrogen

→

(3R, 5S)-6-benzoyloxy-3,5-dihydroxyhexanoic acid tert-butylester

수율 89.0%

용매

methanol water

반응 조건

후처리

1. 1
   기타at −78° C.
2. 2
   기타to react for twenty hours under a hydrogen pressure of 5.0 kg/cm2
3. 3
   추출After extraction of hydrogen
4. 4
   기타condensed
5. 5
   기타purified by silica gel column chromatography

실험 절차

To (S)-6-benzoyloxy-3-oxo-5-hydroxyhexanoic acid tert-butylester (161 mg, 0.50 mmol) and RuBr2(R)-BINAP (4.4 mg, 0.0050 mmol) (BINAP was 2,2′-bisdiphenylphosphino-1,1′-binaphthyl), 2 mL of a methanol-water (10/1) solution was added to completely dissolve the (S)-6-benzoyloxy-3-oxo-5-hydroxyhexanoic acid tert-butylester and RuBr2(R)-BINAP in an argon atmosphere. Hydrogen replacement at −78° C. was performed three times. After the temperature of the resulting mixture had increased to 50° C., the mixture was allowed to react for twenty hours under a hydrogen pressure of 5.0 kg/cm2. After extraction of hydrogen, the mixture was condensed and purified by silica gel column chromatography. As a result, 144.4 mg (89%) of (3R, 5S)-6-benzoyloxy-3,5-dihydroxyhexanoic acid tert-butylester was obtained. The diastereomer ratio determined by high performance liquid chromatography (HPLC) analysis was (3R, 5S):(3S, 5S)=93.5/6.5 (Chiralcel-AD, hexane/isopropanol=95/5, 1.0 mL/min, UV=210 nm. Retention time: (3R, 5S) 28.2 min, (3S, 5S) 42.9 min).

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