Studies on transition-metal complexes containing the scorpionate ligand(I)- Synthesis, characterization and crystal structure of copper(II) complexes with hydrotris[3-{p-methoxyphenyl(pyrazol-1-yl)}]borate

A scorpionate ligand K[HB {pz(An)}(3)](pz(An)= 3-{p-methoxyphenyl} pyrazole ) was prepared, which was reacted with one molar equivalent of Cu(O2CMe)(2) . H2O in THF at room temperature, yielding [Cu(O2CMe) (HB{pz(An))(3))](I). But the reaction of K[HB {pz(An))(3)] with anhydrous CuCl2 afforded CuCl(p z(An)H)(HB)pz(An))(3))(II). The EPR spectra of I and II in benzene solution exhibit a pseudoaxial symmetrical (d(x2-y2))(1) configuration at copper. B oth I and II are characterized by IR, elementary analysis and CV, The cryst al structure of compound If has been determined. Crystals are monoclinic, s pace group P2(1)/c with a = 1. 164 3(2) nm, b = 2. 708 1(5) nm, c = 1. 449 4(3) nm, beta =105.37(3)degrees, V = 4. 406 6(14) nm(3) and Z = 4, with fin al residuals R = 0. 060 4 and R-w = 0. 141 6. The complex shows a distorted square pyramidal copper center, and exhibits a weak intramolecular hydroge n bond, N-H ... Cl, with bond length of Cl ... N 0. 300 9 nm and bond angle of Cl ... H-N 120. 3 degrees.