Solid-state and solution-state coordination chemistry of the zinc triad with the mixed N,S donor ligand bis(2-methylpyridyl) sulfide.
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)(ClO(4))(2), Cd(1)(2)(ClO(4))(2), and Zn(1)(2)(ClO(4))(2).CH(3)CN form mononuclear, six-coordinate species in the solid state with 1 binding in a tridentate coordination mode. Hg(1)(2)(ClO(4))(2) has a distorted trigonal prismatic coordination geometry while Cd(1)(2)(ClO(4))(2) and Zn(1)(2)(ClO(4))(2).CH(3)CN have distorted octahedral geometries. With chloride anions, the 1:1 metal to ligand complexes Hg(1)Cl(2), [Cd(1)Cl(2)](2), and Zn(1)Cl(2) are formed. A bidentate binding mode that lacks thioether coordination is observed for 1 in the four-coordinate, distorted tetrahedral complexes Zn(1)Cl(2) and Hg(1)Cl(2). [Cd(1)Cl(2)](2) is dimeric with a distorted octahedral coordination geometry and a tridentate 1. Hg(1)Cl(2) is comprised of pairs of loosely associated monomers and Zn(1)Cl(2) is monomeric. In addition, Hg(2)(1)Cl(4) 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 (1)H NMR spectra of [Hg(1)(2)](2+) and [Hg(1)(NCCH(3))(x)()](2+) reveal (3)(-)(5)J((199)Hg(1)H) due to slow ligand exchange found in these thioether complexes. Implications for use of Hg(II) as a metallobioprobe are discussed.
Berry
Steven M
SM
Department of Chemistry, The College of William and Mary, Williamsburg, Virginia 23187-8795, USA.
Bebout
Deborah C
DC
Butcher
Raymond J
RJ
D002104:Cadmium / Q000737:chemistry*; D002712:Chlorides / Q000737:chemistry; D018360:Crystallography, X-Ray; D008024:Ligands; D009682:Magnetic Resonance Spectroscopy; D008628:Mercury / Q000737:chemistry*; D008958:Models, Molecular; D008968:Molecular Conformation; D015394:Molecular Structure; D009942:Organometallic Compounds / Q000138:chemical synthesis*; D011725:Pyridines / Q000737:chemistry*; D013440:Sulfides / Q000737:chemistry*; D013816:Thermodynamics; D015032:Zinc / Q000737:chemistry*
D002712:Chlorides; D008024:Ligands; D009942:Organometallic Compounds; D011725:Pyridines; D013440:Sulfides; D002104:Cadmium; D008628:Mercury; D015032:Zinc