Synthesis, spectroscopic and structural characterization of Cu(II) derivatives of tris(pyrazol-1-yl)methanes

The reaction between CuX2 (X = ClO4, NO3, Cl, Br and CH3COO) and excess of tris(pyrazol-1-yl)methane ligands L (L = CH(pz)(3). CH(4-Mepz)(3), CH(3,5-Me(2)pz)(3), CH(3,4,5-Me(3)pz)(3) or CH(3-Mepz)(2)(5-Mepz)) yields [CuX2(L)], [{CuX2}(3)(L-2)(2)] or [Cu(L-2)]X-2-type complexes. The ligand to metal ratio is dependent on the number and disposition of the Me substituents on the azole-type ligand and mainly on the nature of the counter-ion X. All complexes have been characterized in the solid state as well as in solution (IR and UV spectra, and conductivity determinations). The solid-state structures of [Cu{(3,5-Me(2)pz)(3)CH}(2)](NO3)(2), [Cu{(3,5-Me(2)pz)(3)CH}(2)](ClO4)(2).0.5H(2)O, [Cu{(3,4,5-Me(3)pz)(3)CH}(2)](NO3)(2).H2O, [Cu{(4-Mepz)(3)CH}(2)]Br-2.3H(2)O have been determined by single crystal X-ray studies. (C) 2002 Elsevier Science B.V. All rights reserved.