反応 #481595

ord-3d2e707a52874193af73980bbf7a3e3a

反応条件

温度
-20°CELSIUS
詳細条件
See reaction.notes.procedure_details.

後処理

  1. 1
    workup.ADDITIONthe addition the solution
  2. 2
    workup.STIRRINGthe reaction mixture is stirred for an hour at −20° C
  3. 3
    温度After slow heating to room temperature the reaction mixture
  4. 4
    抽出the aqueous phase is extracted with ether
  5. 5
    乾燥the organic phase is dried with magnesium sulfate
  6. 6
    workup.DISTILLATIONThe solvent is distilled off in a rotary evaporator
  7. 7
    その他the residue is purified on silica gel with petroleum ether/ethyl acetate (9:1)

実験手順

3.3 g (0.01 mol) 2,5-bis-tert.-butyloxycarbonylamino-bromobenzene from step A are dissolved in 100 ml of water-free tetrahydrofuran under argon. Gradually 17 ml of a 1.6 molar methyl lithium ether solution (0.03 mol) are added. The reaction mixture is cooled to −20° C. Subsequently 7 ml of 1.5 molar t-butyl lithium solution (0.01 mol) are added gradually. After ending the addition the solution is stirred for 30 minutes at −20° C. Subsequently 1.2 g of dimethylformamide (0.02 mol) are added and the reaction mixture is stirred for an hour at −20° C. After slow heating to room temperature the reaction mixture is hydrolyzed with water and then poured into ether, the aqueous phase is extracted with ether and then the organic phase is dried with magnesium sulfate. The solvent is distilled off in a rotary evaporator and the residue is purified on silica gel with petroleum ether/ethyl acetate (9:1).

出典

DOI: 10.6084/m9.figshare.5104873.v1特許: US06602302B1uspto-grants-2003_08