Coordination polymers are playing an increasingly important role in the field of inorganic chemistry. Of particular interest is the use of Cu(II) carboxylates to assemble new compounds involving various bridging ligands for the formation of coordination polymers. A new [Cu(is)2(pyz)] n coordination compound has been synthesized by the reaction of Co(II) isobutyrate with pyrazine (pyz) ligand in acetonitrile. A single-crystal X-ray diffraction analysis shows that the pepared compound is a one-dimensional coordination polymer in which the [Cu(is)2] units are connected by pyrazine ligands into chains.