Electrochemical cascade pyrazole annulation and C-H halogenation for the synthesis of 4-halopyrazoles
Haijin Guo, Yunyun Liu, Jie‐Ping Wan
Abstract
The synthesis of 4-halo-functionalized pyrazoles by electrochemical cascade reactions between N,N-dimethyl enaminones and proper hydrazine reagents in the presence of a halogen source is realized at room temperature. The work provides tunable and efficient accesses to 4-chloro- and 4-bromopyrazoles in aqueous THF (tetrahydrofuran) without using any transition metal reagent.
Topics & Concepts
ReagentTetrahydrofuranHalogenationPyrazoleChemistryAnnulationElectrochemistryCascadeHydrazine (antidepressant)HalogenAqueous solutionCombinatorial chemistryMedicinal chemistryOrganic chemistryElectrodeCatalysisAlkylChromatographyPhysical chemistrySolventCatalytic C–H Functionalization MethodsSulfur-Based Synthesis TechniquesSynthesis and Biological Evaluation