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Updated: May 22, 2026

Synthesis of a Water-soluble Metal–Organic Complex Array
Published on: October 8, 2016
Diaqua-bis-(5-carb-oxy-2-ethyl-1H-imidazole-4-carboxyl-ato-κ(2)N(3),O(4))cobalt(II) trihydrate
Abstract:
In the title compound, [Co(C(7)H(7)N(2)O(4))(2)(H(2)O)(2)]·3H(2)O, the Co(II) cation, located on an inversion center, is N,O-chelated by two 5-carboxy-2-ethyl-1H-imidazole-4-carboxylate anions and further coordinated by two water mol-ecules in a distorted octa-hedral geometry. Only one carboxy group of the anion is deprotonated, and the two carboxyl groups of the same anion are linked via an intra-molecular O-H⋯O hydrogen bond. One of the lattice water mol-ecules is located on an inversion center, its H atom equally disordered over two positions. One of H atoms of another lattice water mol-ecules is also equally disordered over two sites. Water H atoms and the amino H atom all are involved in an inter-molecular hydrogen-bonded network in the crystal.
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