A series of putative mono- and binuclear copper(II) complexes, of general formulas [CuL](ClO4) and [Cu2L](ClO4)(2), respectively, have been synthesized from lateral macrocyclic ligands that have different compartments, originated from their corresponding precursor compounds (PC-1, 3,4:9,10-dibenzo-1,1 2-[N, N'-bis{(3-formyl-2-hydroxy-5-methyl)-benzyl}diaza]-5,8-dioxacyclotetradecane; and PC-2, 3,4:9,10-dibenzo-1,12-[N,N'-bis{(3-formyl-2-hydroxy-5-methyl)-benzyl}diaza]-5,8-dioxacyclopentadecane). The precursor compound PC-1 crystallized in the triclinic system with space group P (1) over bar. The mononuclear copper(II) complex [CuL1a) (ClO4) is crystallized in the monoclinic system with space group P2(1)/c. The binuclear copper(II) complex [Cu2L2c](ClO4)(2) is crystallized in the triclinic system with space group (P) over bar1; the two Cu ions have two different geometries. Electrochemical studies evidenced that one quasi-reversible reduction wave (E-pc = -0.78 to -0.87 V) for mononuclear complexes and two quasi-reversible one-electron-transfer reduction waves (E-pc(1) = -0.83 to -0.92 V, E-pc(2) = -1.07 to -1.38 V) for binuclear complexes are obtained in the cathodic region. Room-temperature magnetic-moment studies convey the presence of antiferromagnetic coupling in binuclear complexes [mu(eff) = (1.45-1.55)mu(B)], which is also suggested from the broad ESR spectra with g = 2.10-2.11, whereas mononuclear complexes show hyperfine splitting in ESR spectra and they have magnetic-moment values that are similar to the spin-only value [mu(eff) = (1.69-1.72)mu(B)]. Variable-temperature magnetic susceptibility study of the complex shows that the observed -2J value for the binuclear complex [Cu2L1b] (ClO4)(2) is 214 cm(-1). The observed initial rate-constant values of catechol oxidation, using complexes as catalysts, range from 4.89 x 10(-3) to 5.32 x 10(-2) min(-1) and the values are found to be higher for binuclear complexes than for the corresponding mononuclear complexes.