నైరూప్య

Synthesis and Spectral Studies of Nickel (II) Complexes with 18-Membered Macrocyclic Ligand Derived from Malonodihydrazide and Diketones

Raman Kumar, Kumari Anita and Kumari Upma Jain

18-Membered macrocyclic complexes of Ni (II) of the type [Ni(H2Cz)] have been synthesized and characterized on the basis of spectral, magnetic and conductivity studies. The macrocyclic ligands H4Cz are tetrabasic having four imido hydrogen but behave in a dibasic manner. Out of eight nitrogens, four are imido and four are imino. Ligands utilize four imido nitrogens for square planar coordination forming four 7 : 6 : 7 : 6 chelate rings giving rise to a 18 membered macrocyclic framework. Nickel (II), complexes having red color are diamagnetic. Low molar conductivity values in the range 7-12 ohm-1 cm2 mol-1 suggest complexes to be non-electrolytic in nature. High dilute conditions have been employed in the synthesis of macrocyclic complexes in order to dispense with polymerization reaction.