Poly[[aqua-μ₃-2,2-dimethylmalonato-copper(II)] monohydrate] and poly[aqua-μ₃-2,2-dimethylmalonato-copper(II)]

Abstract

The coordination mode of the dimethylmalonate ligand in the two title Cu(II) complexes, {[Cu(C(5)H(3)O(4))(H(2)O)]·H(2)O}(n), (I), and [Cu(C(5)H(3)O(4))(H(2)O)](n), (II), is the same, with chelated six-membered, bis-monodentate and bridging bonding modes. However, the coordination environment of the Cu(II) atoms, the connectivity of their metal-organic frameworks and their hydrogen-bonding interactions are different. Complex (I) has a perfect square-pyramidal Cu(II) environment with the aqua ligand in the apical position, and only one type of square grid consisting of Cu(II) atoms linked via carboxylate bridges to three dimethylmalonate ligands, with weak hydrogen-bond interactions within and between its two-dimensional layers. Complex (II) has a coordination geometry that is closer to square pyramidal than trigonal bipyramidal for its Cu(II) atoms with the aqua ligand now in the basal plane. Its two-dimensional layer structure comprises two alternating grids, which involve two and four different dimethylmalonate anions, respectively. There are strong hydrogen bonds only within its layers.

Impacts of Alkali Metals on the Structures and Properties of Fe(III) Heterometallic Cyclobutane-1,1-dicarboxylate Complexes

“…The use of dicarboxylic acids allows one to obtain coordination mono- and polynuclear compounds with various structures, with one of the most notable examples of such ligands presented by anions of malonic acid. By varying the substituents in the methylene group of malonic acid, it is possible to change the structure and properties of the resulting compounds, which was previously demonstrated for homometallic complexes of manganese­(II), − cobalt­(II), − nickel­(II), , copper­(II), − etc. Moreover, the structure of malonate complexes of transition metals, and hence their properties, can be changed by introducing atoms of s-, d-, or f-elements into a compound. − To date, vast data on the synthesis, structural features, and properties of transition metal complexes (with the exception of iron) with anions of substituted malonic acids and atoms of s-elements have been collected.…”