title: Spectroscopic characterization of chromium(III), manganese(II) and nickel(II) complexes with a nitrogen donor tetradentate, 12-membered azamacrocyclic ligand.
abstract: The complexes of Cr(III), Mn(II) and Ni(II) were synthesized with macrocyclic ligand i.e. 5,11-dimethyl-6,12-diethyl-dione-1,2,4,7,9,10-hexazacyclododeca -1,4,6,10-tetraene. The ligand (L) was prepared by [2+2] condensation reaction of 2,3-pentanedione and semicarbazide hydrochloride. These complexes were found to have the general composition [Cr(L)X(2)]X and [M(L)X(2)] (where M=Mn(II) and Ni(II); X=Cl(-), NO(3)(-), (1/2)SO(4)(2-), NCS(-) and L=ligand [N(6)]). The ligand and its transition metal complexes were characterized by the elemental analysis, molar conductance, magnetic susceptibility, mass, IR, electronic and EPR spectral studies. On the basis of IR, electronic and EPR spectral studies, an octahedral geometry has been assigned for these complexes except sulphato complexes which are of five coordinated geometry.
authors.affiliation: Department of Chemistry, Zakir Husain College, University of Delhi, J.L. Nehru Marg, New Delhi 110002, India. schandra_00@yahoo.com
authors.forename: Sulekh
authors.initials: S
authors.lastname: Chandra
authors.forename: Meenakshi
authors.initials: M
authors.lastname: Pundir
mesh_terms: D002857:Chromium / Q000737:chemistry; D004553:Electric Conductivity; D004578:Electron Spin Resonance Spectroscopy; D004583:Electrons; D008024:Ligands; D047028:Macrocyclic Compounds / Q000737:chemistry*; D008280:Magnetics; D008345:Manganese / Q000737:chemistry; D019216:Metals, Heavy / Q000737:chemistry*; D009532:Nickel / Q000737:chemistry; D009584:Nitrogen / Q000737:chemistry*; D009942:Organometallic Compounds / Q000737:chemistry*; D013055:Spectrophotometry, Infrared
chemical_list: D008024:Ligands; D047028:Macrocyclic Compounds; D019216:Metals, Heavy; D009942:Organometallic Compounds; D002857:Chromium; D008345:Manganese; D009532:Nickel; D009584:Nitrogen