反应 #50685

ord-10b426337f1a4e8d857367c3d6f38ad1

反应条件

详细条件
See reaction.notes.procedure_details.

后处理

  1. 1
    workup.ADDITIONAfter the addition
  2. 2
    workup.STIRRINGwas stirred for 30 minutes at room temperature
  3. 3
    萃取extracted with DCM
  4. 4
    洗涤The combined organic layers were washed with water
  5. 5
    干燥dried over magnesium sulfate
  6. 6
    其他evaporated in vacuo
  7. 7
    其他The residue was purified by flash column chromatography (silica gel, DCM/ethyl acetate, 5:1)
  8. 8
    其他affording

实验过程

To a solution of 3-benzoylpyrrole (4.92 g) in 50 ml of dry dimethylformamide was added milled potassium hydroxide (8.06 g). Hydroxylamine-O-sulfonic acid (4.23 g) was added to the suspension in 4 portions over a period of 1 hour with stirring at room temperature. After the addition was completed the reaction mixture was stirred for 30 minutes at room temperature, and subsequently diluted with 50 ml of water and extracted with DCM. The combined organic layers were washed with water, dried over magnesium sulfate and evaporated in vacuo. The residue was purified by flash column chromatography (silica gel, DCM/ethyl acetate, 5:1), affording starting material (1.44 g) and the desired product as the second fraction. Recrystallization from ethyl ether/hexane gave the product as crystals (1.80 g), which was combined with material obtained from a 36.9 mmol scale reaction and recrystallized from DCM/hexane affording 3.20 g of crystals, m.p. 82°-83° C.

来源

DOI: 10.6084/m9.figshare.5104873.v1专利: US05428053uspto-grants-1995_06