反应 #172407

ord-faaff0d414f44e8ab2ca3ea4a367ed71

反应条件

详细条件
See reaction.notes.procedure_details.

后处理

  1. 1
    温度With ice-cooling
  2. 2
    其他does not exceed 10-15° C
  3. 3
    温度The mixture is then cooled and, at 0° C.-5° C.
  4. 4
    workup.STIRRINGThe mixture is stirred briefly
  5. 5
    其他does not exceed 30° C.
  6. 6
    其他does not fall below 25° C
  7. 7
    workup.ADDITIONAfter the addition
  8. 8
    workup.STIRRINGthe mixture is stirred for another 30 min
  9. 9
    其他After phase separation
  10. 10
    萃取the aqueous phase is once more extracted with ethyl acetate
  11. 11
    洗涤The combined organic phases are washed with an aqueous sodium bisulphite solution
  12. 12
    其他The organic phase is removed
  13. 13
    其他evaporated to dryness under reduced pressure
  14. 14
    workup.DISSOLUTIONThe residue is dissolved in dichloromethane
  15. 15
    其他purified by chromatography on silica gel (cyclohexane/ethyl acetate 1:2

实验过程

With ice-cooling, 1.15 l (575 mmol) of a 0.5 molar solution of 9-borabicyclo[3.3.1]nonane in tetrahydrofuran are added to 70.7 g (262 mmol) of the compound from Example 60A (alternative synthesis) such that the internal temperature does not exceed 10-15° C. The mixture is then warmed to RT and stirred at room temperature for 1.5 h. The mixture is then cooled and, at 0° C.-5° C., 653 ml (1.31 mol) of a 2-molar aqueous solution of sodium hydroxide are added. The mixture is stirred briefly, and 296 g (2.51 mol) of a 30% strength hydrogen peroxide solution are then added such that the temperature does not exceed 30° C. and does not fall below 25° C. After the addition has ended, the mixture is stirred for another 30 min. Water and ethyl acetate are added to the reaction mixture. After phase separation, the aqueous phase is once more extracted with ethyl acetate. The combined organic phases are washed with an aqueous sodium bisulphite solution. The organic phase is removed and evaporated to dryness under reduced pressure. The residue is dissolved in dichloromethane and purified by chromatography on silica gel (cyclohexane/ethyl acetate 1:2, then ethyl acetate). This gives 66.5 g (88% of theory) of the desired product.

来源

DOI: 10.6084/m9.figshare.5104873.v1专利: US08846934B2uspto-grants-2014_09