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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·CuCl2·MX2 (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°CuX2 X = Cl(l) or Br(2)) with M(PhCN)2Cl2(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), b = 28.863(4), c = 16.009(1)A, β = 98.71(2)°, V = 4827(1)A3, Z = 4, D c = 1.65 g cm−3 and space group P21/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)A while that of palladium is square plana...

The cation trans -[Ru(bpy) 2 (PPh 3 ) 2 ] 2+ and trans -[Ru(Me 2 bpy 2 ) 2 (py) 2 ] 2+ both contain bipyridine ligands which are distorted because of the crowding of the two chelate units. The hexafluorophosphate salt of the first cation crystallizers in space group P2 1 /n, with a = 11.630(1), b = 20.245(2), c = 11.299(1)A, &#x03B2 = 103.99(1)°, and Z = 2. R = 0.047 for 2396 observed reflections. The hexafluorophosphate salt of the second cation crystallizers in space group C2/m, with a = 18.392(2), b = 11.265(1), c = 13.383(1)A, &#x03B2 = 139.42(2)°, and Z = 2. R = 0.047 for 1403 observed reflections. The Ru of the first cation lies on an inversion center and the Ru of the second cation lies on a special position of 2/m symmetry. The distortions of a number of bipyridine complexes with the trans geometry are analyzed and found to fall into two categories, bowed or twisted. The two complexes of this report were found to have a bowed conformation.

Crystals of the title sulfur compound are orthorhombic, Cmca, with a=9.872 (1), b=9.594 (1), and c=15.488 (1) A, V=1467.0 (4) A3, Z=4, and Dc =1.38 g cm−2. The final refinement using 537 observed reflections for 57 variable gave R=0.025. The non-isomorphous crystals of the selenium analog are also orthorhombic, Cmca, with a=9.300 (1), b=19.724 (1), c=8.064 (1) A, V=1479.1 (4) A, Z=4, and Dc =2.21 g cm−2. Refinement with 48 variables using 447 observed reflections gives R=0.041. In both structures the molecules have 2/m symmetry imposed by the lattice symmetry; the S (or Se) atoms of the central 4-membered ring are located on the rotation axis, and the P, exo S (or Se), and two carbon atoms of the t-butyl group lie on the mirror plane. The central rings are not readily hydrolyzed or oxidized by exposure to air, apparently as a result of steric protection provided by the t-butyl groups.