A novel process for preparing 3-fluoroalkyl-5-pyrazolecarboxylates and carboxylic acids is hereby presented. Easily accesible α-fluorinated ketimines were condensed with oxalyl monochloride derivatives, and the obtained vinamides underwent acid-catalyzed cyclization with substituted hydrazines. This highly efficient protocol can also be used for non-fluorinated C-3 and C-5 substituents.

中文翻译：

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3-氟烷基-5-吡唑羧酸盐和羧酸的新合成途径

因此，提出了制备3-氟烷基-5-吡唑羧酸酯和羧酸的新方法。容易达到的α-氟代酮亚胺与草酰一氯化物衍生物缩合，然后将所得的乙烯基酰胺用取代的肼进行酸催化的环化反应。该高效方案也可用于非氟化的C-3和C-5取代基。