反应详情

18.0 g (71.1 mmol) of 4-Oxo-1-trifluoromethyl-cyclohexanecarboxylic acid methoxy-methyl-amide (68) were dissolved in 350 ml of anhydrous ethanol and 2.96 g (78.2 mmol) of NaBH4 were added portionwise at −70° C. The mixture was then stirred for 1 h at ambient temperature, followed by addition of 500 ml of water. Initially, the pH was then adjusted to pH=4-5 using a 10% aqueous HCl-solution to remove remaining NaBH4. Afterwards, the pH was adjusted to pH=8 using saturated aqueous NaHCO3-solution and the ethanol was evaporated. The residual solution was extracted three times using 300 ml of ethyl acetate each. Afterwards, the organic layer was washed using 300 ml of a saturated aqueous NaCl-solution, dried over MgSO4 and evaporated. Chromatography on silica gel using ethyl acetate/n-heptane yielded 6.00 g of 69 as a colourless oil, containing only one cis/trans isomer of unknown configuration. Rt=0.66 min (Method P).

1. customto remove
2. customthe ethanol was evaporated
3. extractionThe residual solution was extracted three times
4. washAfterwards, the organic layer was washed
5. dry with materialdried over MgSO4
6. customevaporated