Syntheses,Structures And Properties Of Complexes Based On Azole-Based Derivatives Ligands

Transition and rare earth metal ion complexes based on azole-based derivative ligands with various structures and specific optical and magnetism properties etc.,show broad potential application prospects in the fields of coordination chemistry,materials science and biomedicine.In this paper,four kinds of azole-based derivative ligands and their transition or Ln(?)metal complexes were synthesized by normal stirring solution method or hydrothermal method.All complex crystals were obtained.The optical and magnetism properties of these complexes were investigated.The whole work in this thesis can be summarized as follows:1.Four mononuclear lanthanide complexes {[Ln(HTMSA)3(H2O)2][Ln(HTMSA)3(DMF)(H2O)]}·15H2O(Ln = Dy(1),Tb(2),Er(3)and Eu(4))based on 5-azotriazolyl-3-methoxy salicylaldehyde(H2TMSA)were synthesized.Single-crystal X-ray diffraction shows that 1-4 are isostructural and there are two different structural mononuclear molecules in each unit.Experimental results reveal that the H2TMSA solution shows a reversible pH-dependent azo(?)hydrazone isomerization,which is evidenced by density functional theory(DFT)calculations.Magnetic susceptibility measurements reveal that complexes 1 and 2 exhibit single-molecular magnetic properties due to their distinct field-induce alternate current(AC)signals and distinct magnetic relaxation under zero and 2400 Oe dc field,respectively.Their single-molecular magnetic behavior are explained by ab initio calculation.2.Two isomers of 4-azotetrazole-3-aminopyrazole(H2ATP)and 1-tetrazolyl-3-pyrazolyl triazene(H3TPT)have been synthesized by the diazo reaction of 5-amimotetrazole and 3-amimopyrazole under low pH value(pH = 1-2)and nearly neutral condition(pH = 5-6),respectively.Four different structural complexes of[Mn(HATP)2(H2O)4](5),[Zn(HATP)2]·1.5H2O(6),{(H3O)2[Cd3(HATP)4C14]}·11H2O(7)and[Co?Co?2(HTPT)4(H2O)2]·6H2O(8)based on H2ATP and H3TPT ligands were further synthesized.Single-crystal X-ray diffraction shows that complex 5 is a Mn(II)mononuclear structure coordinated by two HATP ligands and four water molecules and HATP-anionic ligands of complex 6 act as mono-and tri-denate ligands and coordinate to Zn(?)ions to give a three-demensional framework structure,as well as each of HATP-anion of complex 7 acts as a tridentate chelating ligand and coordinates to Cd(?)ions to form another three-dimensional framework,complex 8 is a one-dimensional ribbon coordination polymer constructed by a mixed-valence Co(?/?)and HTPT2-ligand.H2ATP and H3TPT exhibit different electronic absorption spectra,which are demonstrated by DFT calculation.Complexes 5-7 emit green fluorescence under UV light irradiation.Complex 8 shows field-induced slow magnetic relaxation from Co(?)ions.3.Three Cu(?),Co(?)and Ni(?)transition metal complexes of[Cu(PBTT)](9),[Co(HPBTT)(PBTT)].(DMF)(10)and[Ni(HPBTT)?]·(CH3CH2OH)(11)based on 1-pyrazolyl-3-benzothiazolyl triazene(H2PBTT)ligand were synthesized.Single-crystal X-ray diffraction reveals that a two-dimensional complex of 9 is constructed by tridentate chelating PBTT2-ligands and Cu(?)ions and two similar mononuclear complexes of 10 and 11 are constructed by H2PBTT ligands and Co(III)/Ni(?)ions.Both complexes of 10 and 11 show two 3D supramolecular frameworks via ?-? stacking and hydrogen bonding interactions.DFT calculation indicates that the maximum absorption peak of H2PBTT ligand comes from the electron transition of the highest occupied molecular orbital(HOMO)to the lowest unoccupied molecular orbital(LUMO).Complexes 9-11 can emit green fluorescence.