Journal article

Synthesis, X-ray crystal structure, thermal and solution studies of a centrosymmetric metal-organic polymer based on proton transfer methodology

Show more…
    13.05.2010
Published in:
  • Journal of Coordination Chemistry. - 2010, vol. 63, no. 18, p. 3175-3186
English A 3-D metal-organic coordination polymer based on pyrazine-2,3-dicarboxylic acid (pzdcH₂) formulated as {[Mn(pzdc)(H₂O)₂] · 2H₂O}n (1), was obtained by the treatment of MnCl₂ · 6H₂O with pzdcH₂, 8-hydroxy quinoline (8-HQ), and 2-amino-4-methyl pyridine (ampy). In this study, we describe the synthesis, elemental analysis, IR spectroscopy, TG analysis, and single X-ray diffraction. The X-ray single crystal structure reveals that the chemical environment around each Mn(II) is a distorted octahedral by participating one nitrogen, five oxygens from three (pzdc)²⁻ and two water molecules, O₅MnN. The centrosymmetric 1-D ladder-like structure of 1 is bridged by oxygens of (pzdc)²⁻, and Mn-pzdc-Mn bonds are the rungs for our ladder structure. In the crystal structure, intermolecular O-H ··· O hydrogen bonds result in the formation of a supramolecular structure, effective for the stabilization of the structure. The thermal decomposition of 1 indicates that it is quite thermally stable. The protonation constants of ampy, 8-HQ and pzdcH₂ as the building blocks of proton transfer systems including pzdcH₂-ampy and pzdcH₂-8-HQ and the corresponding stability constants of these systems were determined by potentiometric study. The stoichiometry and stability constants of complexes of pzdcH₂-ampy and pzdcH₂-8-HQ with Mn²⁺ were investigated by this method in aqueous solution. The results obtained from solution study are comparable with the solid state results.
Faculty
Faculté des sciences et de médecine
Department
Département de Chimie
Language
  • English
Classification
Chemistry
License
License undefined
Identifiers
Persistent URL
https://folia.unifr.ch/unifr/documents/301699
Statistics

Document views: 51 File downloads:
  • fro_sxr.pdf: 100