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Updated: Aug 24, 2026
Palladium N-Heterocyclic Carbene Complexes: Synthesis from Benzimidazolium Salts and Catalytic Activity in Carbon-carbon Bond-forming Reactions
Published on: July 30, 2017
Tris[N-(4-fluorophenyl)pyridine-2-carboxamidato-kappa2N,N']cobalt(III) trihydrate: a novel meridional complex
Jian-Ying Qi1, Qi-Yun Yang, Shu-Sun Chan
1Department of Chemistry, Changsha University of Science and Technology, Changsha, Hunan, People's Republic of China. bcqijy@polyu.edu.hk
Abstract:
The title complex, [Co(C(12)H(8)FN(2)O)(3)].3H(2)O, has been synthesized for the first time. The complex comprises three bidentate ligands containing the pyridine-2-carboxamide stem. The distorted octahedral coordination around the Co atom is formed via the pyridine (py) N atom and the deprotonated amide N atom of each ligand, with the three pyridine rings in a meridional arrangement. For each ligand, the pyridine ring and the carbonyl group are nearly coplanar, with torsion angles in the range 0.4 (3)-4.8 (4) degrees. The Co-N(py) distances [1.9258 (16)-1.9656 (17) A] are shorter than the corresponding Co-N(amide) distances [1.9372 (17)-1.9873 (15) A]. In addition, the Co-N(py) distances are closely related to the magnitudes of the chelate angles, a shorter Co-N(py) distance corresponding to a larger angle. Five intermolecular hydrogen bonds, involving carbonyl O atoms of the ligands and lattice water molecules, lead to the formation of a mesh structure.
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