A series of mono- and binuclear copper(II) complexes have been synthesized using HL1 and other mono- and bidentate ligands (L2) [HL1=N′-[(E)-phenyl(pyridin-2-yl)methylidene]thiophene-2-carbohydrazide, L2=2-benzoyl pyridine (BP), neocuprin, imidazole (ImH) and pyrazine] by a one pot synthesis. These complexes were characterized by routine physico-chemical techniques. The single crystal X-ray structures of 1, 2, 3 and 5 were determined. X-ray single crystal analyses reveal that complex 1 is six coordinated while complex 2 is a penta coordinated complex. Complex 3 is pseudo binuclear while 4 and 5 are binuclear complexes. Intermolecular π…π stacking interactions could be detected in the solid medium and classical H-bonding interactions lead to infinite 1D chains and to an infinite 2D network in 2. Variable temperature magnetic susceptibility data display antiferromagnetic couplings in 3–5. The X-band epr spectra for polycrystalline samples of 3–5 exhibit copper(II) hyperfine structure as well as zero-field splitting which are appropriate for the triplet state of such a dimer. Epr data also indicate antiferromagnetic behavior for binuclear complexes 3–5. Binuclear complexes were also studied using cyclic voltammetry (CV) and differential pulse voltammetry (DPV). The conproportion constant (Kcon) of complexes 3–5 have been evaluated and discussed. Modeling by DFT and TD-DFT is done to elucidate the nature and location of the excited state in superoxide dismutase (SOD) mimics. In addition, antioxidant SOD activity showed that HL1 and its copper(II) complexes possess significant scavenging effect against O2− free radicals.