反应 #467499

ord-f136de486a904972a2deea84bad56575

反应条件

温度
70°CELSIUS
详细条件
See reaction.notes.procedure_details.

后处理

  1. 1
    温度The reaction was heated at 70° C. for a further 40 minutes
  2. 2
    温度to cool to room temperature
  3. 3
    workup.ADDITIONthe temperature was kept below 10° C. by addition of more ice
  4. 4
    萃取The aqueous phase was extracted with dichloromethane (3×200 ml)
  5. 5
    干燥the combined extracts were dried (MgSO4)
  6. 6
    过滤filtered
  7. 7
    其他evaporated
  8. 8
    其他to give the crude product, which
  9. 9
    其他was purified by column chromatography

实验过程

Concentrated sulphuric acid (2.17 ml, 40 mM) was added carefully to a suspension of 3,6-dichloropyridazine (2.11 g, 14.3 mM) in water (50 ml). This mixture was then heated to 70° C. and bicyclo[2.2.1]heptane-1-carboxylic acid (Org. Synth., 59, 85; 2.0 g, 14.3 mM) was added. After ten minutes a solution of silver nitrate (0.48 g, 2.8 mM) in water (5 ml) was added dropwise over two minutes. A solution of ammonium persulphate (9.8 g, 43 mM) in water (20 ml) was added over 20 minutes. The reaction was heated at 70° C. for a further 40 minutes and then allowed to cool to room temperature. The mixture was poured onto ice and basified with concentrated aqueous ammonia; the temperature was kept below 10° C. by addition of more ice. The aqueous phase was extracted with dichloromethane (3×200 ml) and the combined extracts were dried (MgSO4), filtered and evaporated to give the crude product, which was purified by column chromatography using ethyl acetate/hexane mixtures as the eluent to give the title compound (3.4 g). 1H NMR (250 MHz, CDCl3) δ1.49-2.00 (8H, m), 2.17 (2H, m), 2.43 (1H, m), 7.45 (1H, s); MS (ES+) m/e 244 [MH]+.

来源

DOI: 10.6084/m9.figshare.5104873.v1专利: US06303597B1uspto-grants-2001_10