Interest in the design and development of coordination networks reveals permanent growth due to wide range of their potential practical applications. On this line, novel N-donor chelating and bridging ligand systems attract attention as molecular based magnetic materials [1, 2]. Recently, we have shown that 2,3-bis(2-pyridyl)pyrazine (dpp) may coordinate to metal ions in several modes, and thus has the ability to form mono- and dinuclear complexes as well as coordination polymers [3]. In continuation of this investigation we have reported here a novel copper(II) dimer [Cu2(Hdpp)2(ox)(Cl)2(H2O)2]Cl2•6(H2O) (1) and 1D coordination polymer {[Cu(dpp)(SO4)(H2O)2]}n (2), both involving dpp as a protonated cationic or neutral chelate ligand and oxalate or sulfate di-anions as bridges, respectively. The compound 1 crystallizes in the triclinic space group P-1: a = 8.6798(10), b = 10.294(3), c = 12.243(4) Å, α = 69.64(2), β = 72.54(2), γ = 84.33(2)°, whereas the compound 2 crystallizes in the monoclinic space group P21/c: a = 14.4096(4), b = 7.0000(2), c = 21.0565(7) Å, β = 132.193(2)°. In both structures, the metal atoms adjust the square-bipyramidal coordination cores in contrast to previously studied compounds [3], where copper atom adopts square-pyramidal surrounding. The N2O3Cl coordination sphere of Cu(II) atom in 1 (Fig. 1) is composed by two N atoms of chelating monoprotonated Hdpp ligand, two O atoms from oxalate bridging ligand, chlorine anion and a weakly coordinated water molecule (Cu1O1w = 2.757(4) Å). The oxalate bridges two Cu(II) atoms in dimer with Cu···Cu intramolecular separation of 5.174(1) Å. In 1D coordination polymer 2 N2O4 surrounding of Cu(II) atom is completed in basal plane by two N atoms of chelate dpp ligand, a water molecule and oxygen of SO42 di-anion. Another water molecule and oxygen atom of two-fold screw axis symmetry related SO42 occupy the apical positions. Thus, sulfate anions serve as bridges and unite the neighboring Cu(II) atoms in zigzag-like chains along the b crystallographic axis (Fig. 2). The Cu···Cu separation along the chain equals 5.1237(9)Å. The OH···O hydrogen bonds additionally link monomeric units within polymer. The π–π stacking of interdigitated aromatic moieties of adjacent chains unite them in supramolecular layers parallel to the ab crystallographic plane.figure