반응 #333217

ord-8738c4ec8dc447b684710ede3a89b834

반응 조건

상세 조건
See reaction.notes.procedure_details.

후처리

  1. 1
    기타The reaction was purged with argon
  2. 2
    온도then heated
  3. 3
    온도at reflux for 3 h
  4. 4
    온도heating
  5. 5
    기타The same reaction
  6. 6
    세척washed with water and brine
  7. 7
    건조dried over MgSO4
  8. 8
    농축concentrated
  9. 9
    기타The residue was purified by silica gel chromatography with 5% to 50% EtOAc/heptane

실험 절차

To a suspension of 6-bromo-1H-indazole (600 mg, 3.05 mmol) in toluene (18 ml) and 1,2-dimethoxyethane (6 ml) were added tributyl(vinyl)tin (1.33 ml, 4.57 mmol) and PdCl2(PPh3)2 (214 mg, 0.31 mmol). The reaction was purged with argon then heated at reflux for 3 h. Additional tributyl(vinyl)tin (0.66 ml, 2.28 mmol) and PdCl2(PPh3)2 (107 mg, 0.15 mmol) were added and heating was continued for 1 h. The same reaction was performed on an additional batch of 6-bromo-1H-indazole (200 mg, 1.02 mmol) and the two crude batches were combined. The reactions were diluted with ethyl acetate, washed with water and brine, dried over MgSO4 and concentrated. The residue was purified by silica gel chromatography with 5% to 50% EtOAc/heptane to isolate 350 mg (60%) of 6-vinyl-1H-indazole as a yellow solid. 1H NMR (CDCl3, 300 MHz): δ (ppm) 8.07 (s, 1H), 7.72 (d, J=8.3 Hz, 1H), 7.48 (s, 1H), 7.35 (d, J=8.3 Hz, 1H), 6.85 (dd, J=17.4, 11.0 Hz, 1H), 5.86 (d, J=17.4 Hz, 1H), 5.35 (d, J=11.0 Hz, 1H).

출처

DOI: 10.6084/m9.figshare.5104873.v1특허: US08658646B2uspto-grants-2014_02