| 摘要 |
Preparation of pyrazoles involves reacting hydrazine derivative or its salts with acetalized 1,3-dicarbonyl compounds and purifying by distilling. Preparation of pyrazoles of formula (I) comprises reacting hydrazine (derivative) or its salts of formula (II) with bisacetals of formula (III), where the hydrazine is reacted with acetalized 1,3-dicarbonyl compounds, distilling, neutralizing the organic phase, extracting, distilling off the volatiles and distilling again. R<1>-R<4> = H, (cyclo)aliphatic, araliphatic or aromatic, or R<1> = halogen, nitrile or OR<7> and R<4> is C(O)R<8>; and R<7>, R<8> = (cyclo)aliphatic, araliphatic or aromatic.
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