反应详情

To a solution of tert.-butyl 4-(2,2-dimethyl-5-oxo-1,3-dioxolan-4-yl)-3-oxobutanoate (16.30 g, 60.08 mmol) in a mixed solvent of toluene (120.0 ml) and ethanol (60.0 ml), sodium methoxide (4.91 g, 79.10 mmol) was dropwise added at 0° C. in an argon atmosphere and stirred for 30 minutes. After dropwise adding 1N hydrochloric acid (80.5 ml), the mixture was stirred at 0° C. for 10 minutes. After evaporating off the most of the organic solvent under reduced pressure, the mixture was extracted with ethyl acetate and washed with a saturated saline and a phosphate buffer (pH 7.0). The organic layers were combined, dried over sodium sulfate and concentrated under reduced pressure. The residue was subjected to silica gel column chromatography (hexane:acetone=2:1) to give pure 1-ethyl 6-tert.-butyl 2-hydroxy-4-oxoadipate (14.02 g, 53.85 mmol). Yield, 89.6%.

1. stirringthe mixture was stirred at 0° C. for 10 minutes
2. customAfter evaporating off the most of the organic solvent under reduced pressure
3. extractionthe mixture was extracted with ethyl acetate
4. washwashed with a saturated saline
5. dry with materialdried over sodium sulfate
6. concentrationconcentrated under reduced pressure