One-dimensional copper(II) coordination polymers based on carboxylate anions and rigid pyridyl-donor ligands

Two copper(II) compounds named [Cu₂(μ-O₂CCH₂C₄H₃S)₄(bipy)]_n (1) and [Cu₂(O₂CCH₂C₄H₃S)₄(bpe)₂]_n (2) [(O₂CCH₂C₄H₃S) = 3-thiopheneacetate anion; bipy = 4,4′-bipyridine and bpe = 1,2-bis(4-pyridyl)ethylene] have been synthesized and structurally characterized by single crystal X-ray diffraction analysis. Compound 1 consists of binuclear paddle wheel SBUs connected by bridging bipy ligands resulting on a 1D polymeric chain. On the other hand, compound 2 contains two crystallographically independent copper(II) centers coordinated by 3-thiopheneacetate ions in a monodentate fashion and by bpe ligands acting in a bridging mode to form 1D polymeric chains. In both cases, the 1D polymeric chains are linked through non-classical hydrogen bondings C-H···O, that apparently control the crystal packing.