Filling the gap: Chemistry of 3,5-bis(trifluoromethyl)-1H-pyrazoles

Pyrazoles represent important building blocks for the preparation of bioactive compounds and a large variety of materials, due to their rich coordination chemistry. Unusual and interesting properties may be imparted to molecules embodying highly fluorinated pyrazoles, but to date only few examples of polyfluorinated pyrazoles have been described. In this work we report an improved preparation of 3,5-bis(trifluoromethyl)-1H-pyrazole, the subsequent transformation into hitherto unknown 4-functionalized (F, Cl, Br, I, NO2, NH2) derivatives and the evaluation of selected chemical and physical properties of these compounds. (C) 2012 Elsevier B.V. All rights reserved.