반응 #11322

반응 방정식

3,6-dichloro-4-cyclobutylpyridazine

benzoic hydrazide

triethylamine hydrochloride

→

title compound

수율 34.0%

6-Chloro-7-cyclobutyl-3-phenyl-1,2,4-triazolo[4,3-b]pyridazine

수율 34.0%

용매

p-xylene

반응 조건

후처리

1. 1
   온도heated
2. 2
   온도at reflux under a stream of nitrogen for 24 hours
3. 3
   온도Upon cooling the volatiles
4. 4
   기타were removed in vacuo
5. 5
   기타The residue was partitioned between dichloromethane and water
6. 6
   workup.ADDITIONThe aqueous was basified by the addition of solid potassium carbonate
7. 7
   기타Some dark insoluble material was removed by filtration at this stage
8. 8
   추출The aqueous phase was further extracted with dichloromethane (×2)
9. 9
   건조The combined extracts were dried (MgSO4)
10. 10
    여과filtered
11. 11
    기타evaporated
12. 12
    기타The residue was purified by chromatography on silica gel eluting with 5%→10%→25% ethyl acetate/dichloromethane

실험 절차

A mixture of 3,6-dichloro-4-cyclobutylpyridazine from above (55.7 g, 0.27 mol), benzoic hydrazide (41.1 g, 0.30 mol) and triethylamine hydrochloride (41.5 g, 0.30 mol) in p-xylene (0.4 l) was stirred and heated at reflux under a stream of nitrogen for 24 hours. Upon cooling the volatiles were removed in vacuo. The residue was partitioned between dichloromethane and water. The aqueous was basified by the addition of solid potassium carbonate. Some dark insoluble material was removed by filtration at this stage. The aqueous phase was further extracted with dichloromethane (×2). The combined extracts were dried (MgSO4), filtered and evaporated. The residue was purified by chromatography on silica gel eluting with 5%→10%→25% ethyl acetate/dichloromethane to give the title compound, (26.4 g, 34%) as an off-white solid. Data for the title compound: 1H NMR (360 MHz, CDCl3) δ 1.90–2.00 (1H, m), 2.12–2.28 (3H, m), 2.48–2.57 (2H, m), 3.69–3.78 (1H,m), 7.49–7.59 (3H, m), 7.97 (1H, s), 8.45–8.48 (2H, m); MS (ES+) m/e 285 [MH]+, 287 [MH]+.

출처