One-Pot Synthesis of CF₃-Substituted Pyrazolines/Pyrazoles from Electron-Deficient Alkenes/Alkynes and CF₃CHN₂ Generated in situ: Optimized Synthesis of Tris(trifluoromethyl)pyrazole

The [3+2] cycloaddition of CF₃CHN₂, generated in situ, with electron-deficient alkenes/alkynes affords CF₃-substituted pyrazolines/pyrazoles in quantitative yields. The one-pot three-component reaction between CF₃CH₂NH₂•HCl, NaNO₂, and the substrate proceeds at room temperature in dichloromethane/water.

Slobodyanyuk E. Y.; Artamonov O. S.; Shishkin O. V.; Mykhailiuk P. K.
Eur. J. Org. Chem. 2014, 12, 2487-2495
DOI: 10.1002/ejoc.201301852