Synthesis and Characterization of a Fluorinated Tris(pyrazolyl)Borate Ligand and its Cobalt, Nickel and Zinc Complexes

Potassium salt of the fluorinated tris(pyrazolyl)borate ligand [HB(3-(CF3)Pz)3]- has been synthesized in a high yield by the reaction of the corresponding pyrazole with KBH4. First, a series of new zinc (II), nickel (II), and cobalt (II) complexes of the fluorinated tris(pyrazolyl)borate ligand were prepared by reaction of the ligand with the corresponding metal chloride in methanol. Characterization of the complexes revealed that the reaction of the zinc salt with the Tp ligand gave a 1:1 metal to ligand complex [MLCl], whereas cobalt and nickel complexes were a 2:1 ligand to metal complex [ML2]. All the compounds prepared in this work were characterized by elemental analysis, thermaland thermogravimetric (TGA)analysis, FT-IR spectroscopy, H1 NMR, C13NMR spectroscopy and mass spectrometry.