反应详情

Into a flask containing methyl 3-acetyl-1H-pyrazole-5-carboxylate (4.0 g, 0.0238 mol) in acetic acid (60 ml), 5% sodium hypochlorite (284 ml, 0.190 mol) was added dropwise at 10-12° C. The mixture was stirred at RT over three nights adding more 5% sodium hypochlorite (177 ml, 0.119 mol in total) during the second and third day. Water was added to the reaction mixture and the product was extracted with ethyl acetate. Organic layer was dried with anhydrous Na2SO4 and concentrated. The crude product was recrystallized twice from n-hexane. Yield 23%. LC-MS: [M+1]=203.5.

1. additionwas added dropwise at 10-12° C
2. extractionthe product was extracted with ethyl acetate
3. dry with materialOrganic layer was dried with anhydrous Na2SO4
4. concentrationconcentrated
5. customThe crude product was recrystallized twice from n-hexane