trans-Bis(5-carb-oxy-2-methyl-1H-imidazole-4-carboxyl-ato-κN,O)copper(II)
Xin Guo1, Yi Liang Li, Ju Xian Wang
1Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences, and Peking Union Medical College, Beijing 100050, People's Republic of China.
Abstract:
In the title compound, [Cu(C(6)H(5)N(2)O(4))(2)], the copper(II) atom lies on an inversion centre and is in an N(2)O(2) four-coordinate environment with a nearly regular square-planar geometry. An extended network of intra-molecular O-H⋯O and inter-molecular N-H⋯O and C-H⋯O hydrogen bonds stabil-izes the crystal structure.
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Isomers are different chemical species that have the same chemical formula. Structural isomerism of coordination compounds can be divided into two subcategories, the linkage isomers and coordination-sphere isomers.
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Stereoisomerism
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Isomers are different chemical species that have the same chemical formula.
Transition metal complexes often exist as geometric isomers, in which the same atoms are connected through the same types of bonds but with differences in their orientation in space. Coordination complexes with two different ligands in the cis and trans positions from a ligand of interest form isomers. For example, the octahedral [Co(NH3)4Cl2]+ ion has two isomers (Figure 1) In the cis...
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