反応 #59633

ord-1ce7539a41534ff092bba385bf3b8874

反応条件

温度
-70°CELSIUS
詳細条件
See reaction.notes.procedure_details.

後処理

  1. 1
    workup.WAITthe mixture is left
  2. 2
    その他to rise to −10° C.
  3. 3
    workup.WAITis left
  4. 4
    workup.STIRRINGstirring for 1 hour 45 minutes at −10° C
  5. 5
    workup.WAITthe mixture is left
  6. 6
    workup.STIRRINGstirring for 1 hour
  7. 7
    その他to rise to −30° C.
  8. 8
    workup.STIRRINGis then stirred overnight
  9. 9
    その他to rise to RT
  10. 10
    その他the THF is evaporated off
  11. 11
    抽出the resulting aqueous phase is extracted three times with EtOAc
  12. 12
    洗浄the organic phase is washed with water, with saturated NaCl solution
  13. 13
    乾燥dried over Na2SO4
  14. 14
    その他the solvent is partially evaporated off
  15. 15
    ろ過the crystalline product is spin-filtered off

実験手順

A solution of 5 g of tert-butyl 4-chloro-3-methylphenylcarbamate in 45 ml of ether is cooled to −70° C. under an argon atmosphere, 30 ml of a 1.5M solution of tert-butyllithium in pentane are added dropwise, the mixture is left stirring for 1 hour while allowing the temperature to rise to −10° C., and is left stirring for 1 hour 45 minutes at −10° C. The reaction mixture is cooled to −70° C., a solution of 5 g of the compound obtained in step A in 25 ml of THF is added dropwise and the mixture is left stirring for 1 hour while allowing the temperature to rise to −30° C., and is then stirred overnight while allowing the temperature to rise to RT. Saturated NH4Cl solution is added to the reaction mixture, the THF is evaporated off, the resulting aqueous phase is extracted three times with EtOAc, the organic phase is washed with water, with saturated NaCl solution and dried over Na2SO4, the solvent is partially evaporated off and the crystalline product is spin-filtered off. 2.6 g of the expected product are obtained; m.p.=254-256° C.

出典

DOI: 10.6084/m9.figshare.5104873.v1特許: US07425566B2uspto-grants-2008_09