反应详情

To a mixture of 4-amino-2,2-dimethylcyclohexanol (1.0 equiv.) in 1.7 M sodium carbonate solution (1.3 equiv.) and THF (1.3 M) was added benzyl chloroformate (1.5 equiv.) slowly at 0° C. After addition, the mixture was stirred at room temperature overnight. TLC (dichloromethane:MeOH=10:1) showed that the reaction was completed. The mixture was filtered and the aqueous layer was extracted with ethyl acetate. The combined organic layers were washed with brine, dried over anhydrous sodium sulfate and filtered. The filtrate was concentrated under vacuum to give crude racemic product, which was purified by silica gel column chromatography (DCM:MeOH=20:1) to afford benzyl (4-hydroxy-3,3-dimethylcyclohexyl)carbamate (110 g, 49.4%) as colorless oil.

1. additionAfter addition
2. filtrationThe mixture was filtered
3. extractionthe aqueous layer was extracted with ethyl acetate
4. washThe combined organic layers were washed with brine
5. dry with materialdried over anhydrous sodium sulfate
6. filtrationfiltered
7. concentrationThe filtrate was concentrated under vacuum
8. customto give crude racemic product, which
9. customwas purified by silica gel column chromatography (DCM:MeOH=20:1)