反应详情

Using the procedure of Example A-1, step 3, a solution of 4-phenyl-3-(4-pyridyl)-3,4-epoxy-2-butanone (step 3) (250 mg, 1 mmol) in ethanol (15 ml) was treated with anhydrous hydrazine (50 mg, 1.5 mmol) and heated to reflux for 4 hours. The crude product was purified by chromatography (silica gel, 1:1 acetone/hexane). The product was recrystallized from ethyl acetate and hexane to give 4-(3-methyl-5-phenyl-1H-pyrazol-4-yl)pyridine (81 mg, 35%) as a crystalline solid: m. p. 212–214° C. Anal. Calc'd for C15H13N3 (235.29): C, 76.57; H, 5.57; N, 17.86. Found: C, 76.49; H, 5.42; N, 17.39.

1. temperatureheated
2. temperatureto reflux for 4 hours
3. customThe crude product was purified by chromatography (silica gel, 1:1 acetone/hexane)
4. customThe product was recrystallized from ethyl acetate and hexane