Preparation, crystal structures and oxidation activity of two novel nickel(II) complexes of tripodal ligand containing coordinated solvent molecules

Abstract

Two novel Ni^II complexes, [Ni(TMPzA)(CH₃CN)(H₂O)]· (ClO₄)₂ (1) and [Ni(TMPzA)(CH₃OH) (NCS)]· (ClO₄) (2), where TMPzA = tris[(3,5-dimethyl-1-pyrazolemethyl)amine], have been synthesized and characterized. Their crystal structures were determined by X-ray diffraction analysis. Both complexes were isolated from the reactions of TMPzA ligand with metal salts, and thiocyanate as the second ligand in CH₃CN solution for (1) and in CH₃OH solution for (2), respectively. The title complexes are mononuclear structures, and which further assembled into a dimer by the intermolecular hydrogen bond in the unit cell, respectively. The solvent molecules participate in coordination. The spectra properties of the two complexes in solution have been further studied and discussed. The oxidation of styrene catalyzed by the title complexes has been studied, and the new complexes show some catalytic activity under the reaction conditions.