Structural and spectral studies of palladium(II) and platinum(II) complexes derived from N,N,N,N-tetradentate macrocyclic ligands

Palladium(II) and platinum(II) complexes having the general composition M(L)] X2 (where M=Pd(II) and Pt(II), L=3,4,12,13-tetraphenyl-2,5,11,14,19,20-hexaaza tricyclo 13.3.1.1.(6-10)] cosa-1(19), 2,4,6,8,10,(20),11,13,15,17-decaene (L1); 3,4,13,14-tetraphenyl-2,5,12,15-tetraaza tricyclo 11,0,0,(6-11)] cosa-1(16),2,4,7,9,6(11),12,14,17, 19-decaene (L2); 2,3,8,9-tetraphenyl-1,4,7,10-tetraaza cyclododeca-1,3,7,9-tetraene (L3) and X=Cl(-)) have been synthesized. The ligands were characterized on the basis of elemental analyses, IR, 1H NMR and EI mass spectral studies while that of the complexes were characterized on the basis of elemental analyses, molar conductance measurements, magnetic susceptibility measurements, IR, and electronic spectral techniques. All the complexes were found to be diamagnetic. The structures consist of monomeric units in which the Pd(II) and Pt(II) atoms exhibit square planar geometry.