Gameiro A.M.F. | Gillard R.D. | Rees N.H. | Schulte J. | Sengül A.

Article | 2001 | Croatica Chemica Acta74 ( 3 ) , pp.641 - 665

Equilibrium constants are given for addition (mol ratio 1:1) of hydroxide to several palladium(II) and platinum(II) cations. [Pt(bpy)2]2+ (bpy: 2,2'-bipyridine) and hydroxide ion form the well-known 1:1 adduct rapidly in water; the rate is given at 25°C by k = 1.6 × 102 mol-1 dm3 s-1. The equilibrium constants for adding hydroxide to [Pt(bpy)2]2+ and to [Pt(3,3'-[2H]2-bpy)2]2+ are the same, but differ considerably from those for [Pt([2H]8-bpy)2]2+ and for [Pt(6,6'-[2H]2-bpy)2]2+ with hydroxide. In this reaction, the infrared spectrum (1700-900 cm-1) of the cation initially [Pt(bpy)2]2+ in the aqueous solution shows distinct changes . . .between pH = 7.0 and pH = 11.0, notably in the aromatic region, where the intensity of the band due to C=N at ca. 1600 cm-1 is much reduced. At pH = 7.0, the methyl groups in [Pt(5,5'-dmbpy)2]2+ (dmbpy: dimethyl-2,2'-bipyridine) or the 4,4'-isomer are equivalent in 1H magnetic resonance but become inequivalent in the 1:1 adducts with hydroxide. In the presence of (-)-methylbenzylamine, both [Pt(terpy)Cl]Cl (terpy: 2,2',2¨-terpyridine) and [Pt(bpy)2]2+ manifest a strong Pfeiffer effect, but not the 'exciton' coupling characteristic of cis-octahedral ions. These observations are interpreted in terms of addition of hydroxide to the bipyridine ligands Daha fazlası Daha az

Guney E. | Yilmaz V.T. | Sengul A. | Buyukgungor O.

Article | 2010 | Inorganica Chimica Acta363 ( 2 ) , pp.438 - 448

[Pd(sac)(terpy)](sac)·4H2O (1), [Pt(sac)(terpy)](sac)·5H2O (2), [PdCl(terpy)](sac)·2H2O (3) and [PtCl(terpy)](sac)·2H2O (4) (sac = saccharinate, and terpy = 2,2':6',2¨-terpyridine) have been synthesized and characterized by elemental analysis, FT-IR, 1H NMR and 13C NMR. In 1 and 2, a tridentate terpy ligand together with an N-coordinated sac ligand form the square-planar geometry around the palladium(II) or platinum(II) ions, while one sac anion remains outside the coordination sphere as a counter-ion. X-ray single crystal studies show that the [M(sac)(terpy)]+ ions in 1 and 2 reside in the centers of a hydrogen bonded honeycomb net . . .work formed by the uncoordinated sac ions and the lattice water molecules. Complexes 3 and 4 are isostructural and consist of a [M(Cl)(terpy)]+ cation, a sac anion and two lattice water molecules. The [M(Cl)(terpy)]+ ions interact with each other via M-M and ?-? stacking interactions and these ? interacted units are assembled to a 2D network by water bridges involving the sac ions and lattice water molecules. Convenient synthetic paths for 1-4 are also presented, and spectral, luminescence and thermal properties were discussed. © 2009 Elsevier B.V. All rights reserved Daha fazlası Daha az

Guney, Emel | Yilmaz, Veysel T. | Sengul, Abdurrahman | Buyukgungor, Orhan

Article | 2010 | INORGANICA CHIMICA ACTA363 ( 2 ) , pp.438 - 448

[Pd(sac)(terpy)](sac)center dot 4H(2)O (1), [Pt(sac)(terpy)](sac)center dot 5H(2)O (2), [PdCl(terpy)](sac)center dot 2H(2)O (3) and [PtCl(terpy)](sac)center dot 2H(2)O (4) (sac = saccharinate, and terpy = 2,2': 6',2 ''-terpyridine) have been synthesized and characterized by elemental analysis, FT-IR, H-1 NMR and C-13 NMR. In 1 and 2, a tridentate terpy ligand together with an N-coordinated sac ligand form the square-planar geometry around the palladium(II) or platinum(II) ions, while one sac anion remains outside the coordination sphere as a counter-ion. Xray single crystal studies show that the [M(sac)(terpy)](+) ions in 1 and 2 re . . .side in the centers of a hydrogen bonded honeycomb network formed by the uncoordinated sac ions and the lattice water molecules. Complexes 3 and 4 are isostructural and consist of a [M(Cl)(terpy)](+) cation, a sac anion and two lattice water molecules. The [M(Cl)(terpy)](+) ions interact with each other via M-M and pi-pi stacking interactions and these p interacted units are assembled to a 2D network by water bridges involving the sac ions and lattice water molecules. Convenient synthetic paths for 1-4 are also presented, and spectral, luminescence and thermal properties were discussed. (C) 2009 Elsevier B. V. All rights reserved Daha fazlası Daha az