Study On The Properties Of The Complexs Based On Di-2-pyridyl Ketone

Three new ligands L¹-L³ were obtained by the in situ reaction of the Di-2-pyridyl Ketone bidentate ligands in this paper.L² can be synthesized by solvothermal method.Di-2-pyridyl Ketone ligands were coordinated by transition metals forming five novel complexes.None of these ligands except the L² ligand exist as free species;they only exist in their respective metal complexes.All crystals were determined by X-ray single diffraction.The formula of five complexs are as following:Ligand L¹:{?py?₂C?CH₂COO?O} Ligand L²:C₂₄H₁₆N₆Ligand L³:C₂₄H₁₇N₅Complex 1:[Co₄?L¹?₄?Me COOH?₂?MeCN?]_n Complex 2:[Fe₄?O??L²?₃·?Cl?₆·3?H₂O?]_n Complex 3:[Fe₄?L³?₂?Cl?₈]_n Complex 4:[Fe₃{?py?₂C?CH₂COO?O}₂?O??Cl?₂]_n Complex 5:[Fe₄{?py?₂CO}{?py?₂CO₂}?Cl?₆]_nStructure analysis suggest that anionic ligand L² was produced by in situ reaction of?py?₂CO ligand and CH₃COOH.L¹ and L³ ligand was obtained by in situ reaction of?py?₂CO ligand and CH₃CN.Coordination complex 1 consists of tetranuclear cobalt cluster structure.It contains a cubane[Co{?py?₂C?CH₂COO??O?}₄]center.The tripie-helicate complex 2,a binuclear iron cluster,is obtained by three L² ligands.Complex 3 is a tetranuclear iron cluster structure,which is coordinatied by two L²ligands.Complex 4 is alternately connected by{Cl?Fe2=O?Cl}and cubic alkane[Fe₄{?py?₂C?CH₂COO??O?}₄]to form a one-dimensional chain structure with the parallel array.It is interesting that the cubic alkane repeating unit in 4 is isomorphic to the structure 1.Complex 5 shows a one-dimensional chain structure with the parallel array.Its ligand comprises 4.2211 and 2.211 coordination modes to give the anions?py?₂CO₂^—and?py?₂C?OH?O^—.Magnetic measurements indicate that Co ions in coordination complex 1 is antiferromagnetic coupling.Complex 2 shows a weak antiferrmagnetic coupling.Complex 4 is a antiferrmagnetic coupling.The ac susceptibility measurement indicate frequency-dependence because in-phase singal?_m'is observed.