Synthesis and Physico‐Chemical Studies on 18‐Membered Octaazamacrocyclic Complexes of Mn(II), Co(II), Ni(II), Cu(II), and Zn(II) Ions

A new series of 18‐membered octaazamacrocyclic complexes [ML1X2] and [ML2X2] (M = Mn(II), Co(II), Ni(II), Cu(II), and Zn(II); X = Cl or NO3) have been synthesized by template condensation of o‐phthalaldehyde with hydrazine hydrate and formaldehyde or acetaldehyde in MeOH. The nature of bonding and the stereochemistry of the complexes have been deduced from elemental analyses, FT‐IR, 1H NMR, EPR, UV spectroscopy, magnetic susceptibility, and conductivity measurements. An octahedral geometry has been suggested for all the complexes and the observed low molar conductance values indicate their non‐ionic nature.