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Updated: Jun 1, 2026

Palladium N-Heterocyclic Carbene Complexes: Synthesis from Benzimidazolium Salts and Catalytic Activity in Carbon-carbon Bond-forming Reactions
Published on: July 30, 2017
catena-Poly[[diaqua-cobalt(II)]-bis-(μ-4-fluoro-benzoato-κO:O')]
1College of Materials Science and Chemical Engineering, Jinhua College of Profession and Technology, Jinhua, Zhejiang 321017, People's Republic of China.
Abstract:
The hydro-thermal reaction of CoCO(3) and 4-fluoro-benzoic acid afforded the title Co(II) complex, [Co(C(7)H(4)FO(2))(2)(H(2)O)(2)](n). The Co(II) atom is located on an inversion center and is coordinated by six O atoms from two water mol-ecules and four μ(2)-carboxyl-ate groups of 4-fluoro-benzoate anions, forming a distorted CoO(6) octa-hedron, with Co-O bond lengths in the range 2.071 (2)-2.130 (2) Å. All adjacent O-Co-O angles are in the range 84.78 (6)-95.22 (6)° and opposite angles are 180.0°. Each μ-carboxyl-ate group of the 4-fluoro-benzoate anions bridges two symmetry-related Co(II) atoms. Hydrogen-bonding inter-actions of the coordinated water mol-ecules further connect the cobalt-carboxyl-ate units, forming layers perpendicular to the a axis. The cobalt-oxygen layers are encased in a sandwich-like fashion by layers of π-stacked 4-fluoro-benzoate anions. Within these layers the benzene rings of the 4-fluoro-benzoate anions are π-stacked, with centroid-centroid distances of 3.432 (4) Å.
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