Template synthesis and spectroscopic studies of highly conjugated tetraiminetetraamide macrocyclic complexes from 1,2-dephenylethane-1,2-dione dihydrazone

A new class of tetraiminetetraamide macrocyclic (Ph(4)[20]tetraene, N8O4, and Ph(6)[20]tetraene, N8O4) complexes have been prepared through the metal ion controlled reaction of 1,2-diphenylethane-1,2-dione dihydrazone (DPEDDH) with succinic acid [ML(1)X(2)] or phthalic acid [ML(2)X(2)] [M = Mn, Co, Ni, Cu or Zn; X = Cl or NO3]. The structures of the complexes have been elucidated on the basis of i.r, H-1-n.m.r, e.p.r. and electronic spectral data and conductance, as well as magnetic, properties. An octahedral geometry is assigned for all the complexes, involving coordination of the all-imine nitrogens.