Five novel copper(II) coordination polymers containing cyanoacetate (cna) anion with various N,N'-ditopic spacers [Cu(cna) 2 (pyz)] n (1), [Cu(cna) 2 (bpy)(H 2 O) 2 ] n (2),[Cu(cna) 2 (dpe)] n (3), [Cu(cna) 2 (dpe)] n (H 2 O) n (4) and [Cu(cna) 2 (bpa)] n (5) (when pyz = pyrazine, bpy = 4,4'-bipyridyl, dpe = 1,2-di(4-pyridyl)ethylene and bpa = 1,2-di(4-pyridyl)ethane) were structurally and spectroscopically characterized. Compound 1 shows 2D sheet structure constructed from µ 2 -1,3(syn,anti) coordinative mode of cyanoacetate and µ 2 -pyz linking adjacent Cu(II) centers. Compound 2 exhibits 1D polymeric chain which is formed by µ 2 -bpy bridging between [Cu(cna) 2 (H 2 O) 2 ] units. Whereas compounds 3-5 reveal 1D ladder-like structures which are built from double-µ 2 -dpe/bpa spacers connecting neighboring Cu(II) cyanoacetate dimers.Weak interactions such as hydrogen bonding and N···π and/or C−H···π interactions join the adjacent layers of 1 or polymeric chains of 2-5 to stabilize overall supramolecular networks. The thermal stabilities of 1-5 were investigated. Interestingly, compound 2 reveals a robust supramolecular framework constructed by 1D polymeric chains during thermal dehydration and rehydration processes, that has been further verified by spectroscopic techniques, elemental analyses, TGA, and XRPD. Moreover, this behavior is not observed in the isomorphous series containing Co(II) and Ni(II) ions. The magnetic properties of 1 and 3 exhibit very weak antiferromagnetic interactions between Cu(II) centers.

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