Molecules, Vol. 29, Pages 5034: Synthesis of Perfluoroalkylated Pyrazoles from α-Perfluoroalkenylated Aldehydes

Fecha de publicación: 25/10/2024
Fuente: Molecules - Revista científica (MDPI)
Molecules, Vol. 29, Pages 5034: Synthesis of Perfluoroalkylated Pyrazoles from α-Perfluoroalkenylated Aldehydes
Molecules doi: 10.3390/molecules29215034
Authors:
Lennart Bunnemann
Christian Wulkesch
Victoria Carina Voigt
Constantin Czekelius

Within this study, we report a simple two-step process for the synthesis of perfluoroalkylated pyrazoles from aliphatic aldehydes. In the photocatalytic first step, the aldehydes are transformed into the corresponding perfluoroalkylated enals, which then undergo nucleophilic attack by hydrazine and subsequent ring closure, providing the fluorinated 3,4-substituted pyrazole products in a 64–84% yield. Using triphenylphosphine and imidazolidinone as organocatalysts, the method is operationally simple and omits heavy metal-containing waste.