Abstract
The binding of group 12 metal ions to bis(2-methylpyridyl) sulfide (1) was investigated by X-ray crystallography and NMR. Seven structures of the chloride and perchlorate salts of Hg(II), Cd(II), and Zn(II) with 1 are reported. Hg-(1)2(ClO4)2, Cd(1)2(ClO 4)2, and Zn(1)2(ClO4) 2·CH3CN form mononuclear, six-coordinate species in the solid state with 1 binding in a tridentate coordination mode. Hg(1) 2(ClO4)2 has a distorted trigonal prismatic coordination geometry while Cd(1)2(ClO4)2 and Zn(1)2(ClO4)2·CH3CN have distorted octahedral geometries. With chloride anions, the 1:1 metal to ligand complexes Hg(1)Cl2, [Cd(1)Cl2]2, and Zn(1)Cl2 are formed. A bidentate binding mode that lacks thioether coordination is observed for 1 in the four-coordinate, distorted tetrahedral complexes Zn(1)Cl2 and Hg-(1)Cl2. [Cd(1)Cl 2]2 is dimeric with a distorted octahedral coordination geometry and a tridentate 1. Hg(1)Cl2 is comprised of pairs of loosely associated monomers and Zn(1)Cl2 is monomeric. In addition, Hg2(1)Cl4 is formed with alternating chloride and thioether bridges. The distorted square pyramidal Hg(II) centers result in a supramolecular zigzagging chain in the solid state. The solution 1H NMR spectra of [Hg(1)2]2+ and [Hg(1)(NCCH 3)x]2+ reveal 3-5J( 199Hg1H) due to slow ligand exchange found in these thioether complexes. Implications for use of Hg(II) as a metallobioprobe are discussed.
Original language | English (US) |
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Pages (from-to) | 27-39 |
Number of pages | 13 |
Journal | Inorganic chemistry |
Volume | 44 |
Issue number | 1 |
DOIs | |
State | Published - Jan 10 2005 |