反应 #11322

反应方程式

3,6-dichloro-4-cyclobutylpyridazine

benzoic hydrazide

triethylamine hydrochloride

→

title compound

收率 34.0%

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

收率 34.0%

溶剂

p-xylene

反应条件

后处理

1. 1
   温度heated
2. 2
   温度at reflux under a stream of nitrogen for 24 hours
3. 3
   温度Upon cooling the volatiles
4. 4
   其他were removed in vacuo
5. 5
   其他The residue was partitioned between dichloromethane and water
6. 6
   workup.ADDITIONThe aqueous was basified by the addition of solid potassium carbonate
7. 7
   其他Some dark insoluble material was removed by filtration at this stage
8. 8
   萃取The aqueous phase was further extracted with dichloromethane (×2)
9. 9
   干燥The combined extracts were dried (MgSO4)
10. 10
    过滤filtered
11. 11
    其他evaporated
12. 12
    其他The residue was purified by chromatography on silica gel eluting with 5%→10%→25% ethyl acetate/dichloromethane

实验过程

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]+.

来源