反应详情

743 mg (2.28 mmol) of caesium carbonate were added to a solution of 667 mg (4.56 mmol) of 2-hydroxy-4,4-dimethylpentanoic acid (racemate) in 8.7 ml of methanol and 1.7 ml of water The reaction mixture was stirred at RT for 60 min and the solvent was then removed under reduced pressure. The residue was dried under high vacuum (4 h) and then taken up in 10 ml of dimethylformamide. At 0° C., 516 μl (4.33 mmol) of benzyl bromide were slowly added dropwise. The reaction mixture was stirred at RT for 12 h, the reaction was terminated by addition of 25 ml of water and the reaction mixture was extracted three times with 20 ml of ethyl acetate. The combined organic phases were dried over magnesium sulphate and filtered, and the solvent was removed under reduced pressure. The residue was purified by flash chromatography (40 g silica cartridge, 35 ml/min, cyclohexane/ethyl acetate gradient). Yield: 584 mg (54% of theory)

1. customthe solvent was then removed under reduced pressure
2. customThe residue was dried under high vacuum (4 h)
3. stirringThe reaction mixture was stirred at RT for 12 h
4. customthe reaction was terminated by addition of 25 ml of water
5. extractionthe reaction mixture was extracted three times with 20 ml of ethyl acetate
6. dry with materialThe combined organic phases were dried over magnesium sulphate
7. filtrationfiltered
8. customthe solvent was removed under reduced pressure
9. customThe residue was purified by flash chromatography (40 g silica cartridge, 35 ml/min, cyclohexane/ethyl acetate gradient)