Synthesis and Physico‐chemical Studies on a 15‐Membered Hexaaza Macrocyclic Ligand Derived from Hydrazine and Its Complexes with Co(II), Ni(II), Cu(II), and Zn(II)

Abstract

The macrocyclic ligand, 1,2,6,9,13,14‐hexaaza‐3,5,10,12‐tetramethylcyclopentadecane‐2,5,9,12‐tetraene (L), has been prepared by the condensation reaction of hydrazine, formaldehyde, ethylenediamine, and 2,4‐pentanedione in 2:1:1:2 molar ratio. Metal complexes of the type [MLX₂] (M = Co(II), Ni(II), Cu(II), and Zn(II); X = Cl or NO₃) have been synthesized by the reaction of L with the corresponding metal salts in methanol. The macrocyclic ligand (L) and its metal complexes have been characterized by elemental analyses, FT‐IR and ¹H and ¹³C NMR spectral studies. The stereochemistry of the metal complexes have been deduced from magnetic moments and band positions in the electronic spectra.

Keywords:

• Macrocyclic ligand
• Hydrazine
• Condensation reaction
• Metal complexes

Acknowledgments

The Chairman, Department of Chemistry, Aligarh Muslim University, Aligarh, India is acknowledged for providing the necessary facilities. The authors are also thankful to the University Grant Commission, New Delhi, India, vide Project No.F.12‐116/2001, for financial support. We thank the Department of Chemistry at Guru Nanak Dev University, Amritsar, India, for magnetic susceptibility measurements.