biostudies-literatureUnknown11(6)Eisen LSTrifluoromethylated pyrazoles and their derivatives are of great interest due to their biological and pharmacological relevance. However, efficient methods for their preparation via late-stage trifluoromethylation strategies remain limited. Herein, we report a practical and efficient method for the direct trifluoromethylation of pyrazoles using in situ generated CF₃ radicals and inexpensive copper-(II) salts as catalysts at room temperature. The method exhibits excellent functional group tolerance. DFT studies support the observed reactivity trends and provide insight into the electronic effects governing CF₃ radical addition. This strategy holds promise for the generation of highly substituted pyrazoles of interest in biomedical and crop-science applications.ACS omega10664-10673https://www.ebi.ac.uk/biostudies/studies/S-EPMC12917629biostudies-literatureCopper-Mediated Late-Stage Radical Trifluoromethylation of Pyrazole-Type Scaffolds.PMC12917629Eisen LSMendez MGriwatz JHGomez-Bengoa ERuf SfalseCopper-Mediated Late-Stage Radical Trifluoromethylation of Pyrazole-Type Scaffolds.Trifluoromethylated pyrazoles and their derivatives are of great interest due to their biological and pharmacological relevance. However, efficient methods for their preparation via late-stage trifluoromethylation strategies remain limited. Herein, we report a practical and efficient method for the direct trifluoromethylation of pyrazoles using in situ generated CF₃ radicals and inexpensive copper-(II) salts as catalysts at room temperature. The method exhibits excellent functional group tolerance. DFT studies support the observed reactivity trends and provide insight into the electronic effects governing CF₃ radical addition. This strategy holds promise for the generation of highly substituted pyrazoles of interest in biomedical and crop-science applications.2026-01-01T00:00:00Z2026 Feb2026-07-16T18:03:15.795Z2026-07-09T11:10:46.582ZS-EPMC129176294172663910.1021/acsomega.5c12212