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New trans-disubstituted macrocyclic ligands (L1), trans-1,8-[N,N'-bis{(3-formyl-2-hydroxy-5-methyl)benzyl}]-1,4,8,11-tetraaza-5,5,7,12,12,14-hexamethylcyclotetradecane, and (L2), 1,8-[N,N'-bis{(3-formyl-2-hydroxy-5-methyl)benzyl}]-4,11-dimethyl-1,4,8,11-tetraaza-5,5,7,12,12,14-hexamethylcyclotetradecane, were synthesized. The ligands were characterized by elemental analysis, IR, 1H and 13C NMR spectral analyses. The ligand L1crystallized as monoclinic in the space group P21/n, and the final R-value was found to be 0.062. Copper(II) and nickel(II) complexes of these ligands were prepared and characterized by elemental analysis, IR, UV–visible, FAB-mass spectral studies. Electrochemical studies of the nickel(II) complexes show one-electron quasireversible reduction around -1.00 to -1.13 V and one-electron quasireversible oxidation around 1.00 to 1.14 V. The copper(II) complexes show one-electron quasireversible reduction around -0.93 to -1.10 V. ESR spectral studies of the copper(II) complexes show hyperfine splitting with a g||value of 2.31, a g?value of around 2.02 and an Avalue of 160 G. The magnetic moment values (µeff) of the Cu(II) complexes fall in the range of 1.71 to 1.72 B.M. at room temperature (298 K). The rate-constant values of the catalytic hydrolysis of p-nitrophenyl phosphate for the copper(II) complexes were in the range 6.3 × 10-3to 12.2 × 10-3min-1and for the nickel(II) complexes in the range 10 × 10-3to 14 × 10-3min-1. The rate-constant values of the catalytic oxidation of catechol to o-quinone were in the range 9.4 × 10-3to 13.4 × 10-3min-1for the copper(II) complexes. The copper(II) and nickel(II) complexes of ligand L2have higher catalytic activity than that of ligand L1.