Heterobimetallic (Pd,pt,cu) Complexes of Hexapyrazolylcyclotriphosphazene Via Simultaneous Geminal (N(2)) and Nongeminal (N(3)) Coordination Modes

by Thomas, K. R. Justin; Chandrasekhar, Vadapalli; Bryan, Clinton Dave; Cordes, A. Wallace

Synthesis and spectroscopy of four heterobimetallic compounds containing the metal centres Cu(II)-Pd(II) and Cu(II)-Pt(II) with the multidentate nitrogen donor ligand hexakis (3,5-dimethyl-pyrazolyl)cyclotriphosphazene, (HPCTP) are reported. The complexes HPCTP center dot CuCl(2)center dot MX(2) (M = Pd, X = Cl (3) or Br (4) and M = Pt. X = Cl (5) or Br (6)) were obtained by treating the metal-containing ligands HPCTP center dot CuX(2) X = Cl(1) or Br(2)) with M(PhCN)(2)Cl(2)(M = Pd or Pt). The electronic absorption spectra and electron paramagnetic resonance data indicate the copper in these compounds has a distorted trigonal bipyramidal geometry. A single crystal X-ray determination of 4 is reported. The crystals of 4 are monoclinic with a = 10.570(2), h = 28.863(4), c = 16.009(1); 1, beta = 98.71(2)degrees, V = 4827(1) angstrom(3), Z = 4, D(c) = 1.65 g cm(-3) and space group P2(1)/c. The geometry about copper is trigonal bipyramidal with mean distances of Cu-N(pz) = 1.987(13), Cu-N(ctp) = 2.352(11) and Cu-Cl = 2.315(10)angstrom while that of palladium is square planar with distances of Pd-N(pz) = 2.045(11) and Pd-Br = 2.384(6). While copper is coordinated through two nongeminal pyrazolyl nitrogen atoms and a cyclophosphazene ring nitrogen atom, coordination to palladium is through geminal pyrazolyl nitrogen atoms.

Journal of Coordination Chemistry
Start Page
1029-0389; 0095-8972