Synthesis and characterization of cadmium, copper and zinc complexes with scorpionate ligand hydrotris[3-(p-anisyl)-5-methylpyrazol-1-yl]borate [HB{pz(An,Me))(3)]. X-ray structure of [Cd(OAc)(Hpz(Me,An))(HB{pz(An,Me)}(3))]center dot CH2Cl2

A series of new scorpionate complexes, CdCl(Hpz(Me,An))(HB{pz(An,Me)}(3)) ( 1), [Cd(OAC)(Hpz(Me,An))(HB(pz(An,Me)}(3))]. CH2Cl2 (2), ZnCl(HB{pz(An,Me)} (3)) (3), Zn(OAc)(HB( pz(An.Me)}(3)) (4), Cu(OAc)(Hpz(Me,An))(HB {pz(An.Me) }. CH2Cl2 (5) and [CuCl(Hpz(Me.An))(HB{pz(An.Me)}(3))]. CH2Cl2 (6), were pr epared by reacting MX2 (M = Cd2+, Zn2+, Cu2+; X = Cl-, OAc-) with ligand, K [HB{pz(An.Me)}(3)] [pz(An.Me) = 3-(p-anisyl)-5-methylpyrazolyl]. The zinc i on in complexes 3 and 4 are four-coordinate, while copper and cadmium is fi ve-coordinated with an additional substituted pyrazole, Hpz(Me,An), in 1, 2 , 5 and 6. The infrared bands v(as)(CO2) and v(s)(CO2) indicate acetate is an unidentate ligand in 2 and 4, but a bridging one or an intermediate mode between unidentate and bidentate ligand in 5. The H-1 NMR spectra of 1 and 2 show threefold symmetry in solution. The ESR spectra of 5 and 6 in CH2Cl 2 exhibit a pseudoaxial symmetrical {d(x2)-(y2)}(1) configuration at copper . The single crystal structure of 2 shows that the coordination environment around Cd2+ is a distorted square pyramidal. with a N atom of tridentate H B(pz(An.Me))(3) apical. The acetate acts as a unidentate ligand, and an int ramolecular N-H . . .O hydrogen bond exists between the uncoordinated oxyge n of acetate and the pyrazolic proton. (C) 2001 Elsevier Science B.V. All r ights reserved.