The reactions of copper(II) chloride dihydrate and three bulky Schiff base ligands derived from rimantadine and salicylaldehyde (or methoxy-substituted salicylaldehydes), generated C38H48CuN2O2(1), C40H52CuN2O4(2), and C40H52CuN2O4(3), respectively. These complexes were characterized by infrared spectra, UV–vis, elemental analysis and molar conductance. X-ray single-crystal diffraction analysis reveals that1has two different spatial configurations,1aand1b. For1a, each asymmetric unit consists of one mononuclear copper(II) molecule. For1b, each asymmetric unit consists of two copper(II) mononuclear molecules. All the complexes crystallize in the monoclinic system,P21/cspace group for1aand2;P21/nspace group for1b;C2/cspace group for3. Each complex for1–3consists of one copper(II) and two corresponding deprotonated ligands. The central copper(II) in all complexes is four-coordinate via two nitrogens and two oxygens from the corresponding Schiff base ligands. The geometry around copper in1a,1b,and2is distorted square planar, but square planar in3. [ABSTRACT FROM AUTHOR]