New square-planar bis(macrocyclic)dinickel (II) complexes containing phenylene bridges between 16-membered pentaaza macrocyclic subunits have been synthesized via in situ one pot template condensation reaction of aromatic nitrogen-nitrogen linker (R= 1,4-phenylenediamine; benzidine; 4,4'-diaminodiphenylmethan; 4,4'-diaminodiphenylether; 4,4'-diaminodiphenylsulfon), formaldehyde, bis(1,3-diaminopropane) nickel(II) perchlorate and 1,3-dibromopropane in a 1:4:2:2 molar ratio results in the formation of new series of binuclear nickel(II) complexes; 1-phenyl- (1); 1,1'-phenyl- (2); 1,1'-diphenylmethan- (3); 1,1'-diphenylether- (4); 1,1'-diphenylsulfon- (5) bis(1,3,7,11,15-pentaazacyclohexadecane) nickel(II)), {[Ni([16]aneN(5))](2)R}(ClO4)(4 ''). The formation of the macrocyclic framework and the mode of bonding of the complexes have been confirmed by data obtained from elemental analyses, FAB, UV-vis, FIF-IR, H-1 NMR, electronic spectral studies, conductivity and magnetic susceptibility measurements. These complexes have been found to be effective catalysts for the selective oxidation of cyclohexene to 2-cyclohexene-1-one and 2-cyclohexene-2-ol with molecular oxygen as the oxidant. (C) 2007 Elsevier BX All rights reserved.