反应详情

4-[1-sec-butyl-3-(5-chloro-2-thienyl)-1H-pyrazol-4-yl]pyridine-N-oxide (6.1 mmol) was stirred in 20 mL of phosphorous oxychloride at 120° C. for 5 h. The solvent was then evaporated and the residue was treated with methanol and evaporated again. The residue was purified by chromatography on silica gel (hepthane:ethyl acetate 5:1 to 3:1) to afford 623 mg of 2-Chloro-4-[1-sec-butyl-3-(5-chloro-2-thienyl)-1H-pyrazol-4-yl]pyridine (29% yield).

1. customThe solvent was then evaporated
2. additionthe residue was treated with methanol
3. customevaporated again
4. customThe residue was purified by chromatography on silica gel (hepthane:ethyl acetate 5:1 to 3:1)