The Schiff Base Of O-Vanillin With Ethanolamine Metal Complexes:Syntheses,Structures And Properties

Schiff bases are a class of organic compounds containing imines or methylamines with carbon nitrogen double bond(>C=N-).They were widely used in medicine,catalysis,anticorrosion and photochromism.In this thesis,nine heteronuclear metal complexes were obtained by using o-vanillin ethanolamine Schiff base ligand to coordinate with transition metals(Mn,Fe,Ni)and alkali metals(Li,Na,K);four homonuclear metal complexes were obtained by coordinating of the ligand with rare earth ions(Tb,Er,Gd,Tm).The magnetic,electrochemical and fluorescence properties of some metal complexes were studied.The main work of this thesis is as follows:1.Five novel metal complexes were synthesized by the reactions of o-vanillin ethanolamine Schiff base ligand with Mn and alkali metals(Li,Na,K):[Li₂Mn^?Mn₆^?(?₄-O)₂(L)₆(?₂-Cl)₆](1),[Na₂Mn^?Mn₆^?(?₄-O)₂(L)₆(?₂-Cl)₆](2),[K₂Mn^?Mn₆^?(?₄-O)₂(L)₆(?₂-Cl)₆](3),[Na₂Mn^?Mn₆^?(?₄-O)₂(L)₆(OAc)₂(N₃)₄]·2DMF(4),{Na₂Mn^?Mn₆^?(?₄-O)₂(L)₆(OAc)₄[Fe(CN)₅NO]₂}(5).The structures of metal complexes 1-5 were characterized.The magnetic properties of complexes 2,4 and 5 were studied,and the electrochemical properties of complex 5 were also studied.Single crystal structures analysis show that complexes 1-5 are polynuclear complexes with[M₂Mn^?Mn₆^?](M=Li,Na,K)as metal skeleton.The metal skeleton presents a double capped dumbbell structure.Complexes 1-3 are isomorphic complexes which are only different from alkali metals.Complex 4 is obtained by the coordination of two OAc^-and four N₃^-,while complex 5 is obtained by the substituted coordination of four OAc^-molecules with two[Fe(CN)₅NO]^2-.In complexes 1-5,hydrogen bonds and?-?Stacking interactions connect to form three-dimensional supramolecular structures.2.Two Fe-based complexes{Na Fe₄(?₄-O)(L)₄(?₂-Cl)[Fe(CN)₅NO](H₂O)(DMF)₂}(6),{Na Fe₄(?₄-O)(L)₄(?₂-OEt)[Fe(CN)₅NO](H₂O)(DMF)₂}(7)with metal skeleton[Na Fe₄]were successfully systhesized.The ligand firstly reacts with Mn ion,then the Ni ion and Li ion were added to the solutions respectively,and two novel heteronuclear complexes 8-9[Mn₂Ni(L)₂(OAc)₃(N₃)(DMF)₂](8),[Li₂Mn₆(?₄-O)₃(L)₆(?₂-OMe)₆(?₂-OH)₂(?₂-OH₂)](9)were successfully systhesized.The structures of complexes 6-9 were characterized.The XPS spectras of complexes 6-7 show that there are two valence states of Fe²⁺and Fe³⁺in the complexes.Complex 8 was proved to be a heteronuclear metal complex with^[Mn?Ni?Mn?]as metal skeleton.The magnetic properties of complexes 6-9 were studied,and the results show that all metal ions are antiferromagnetic interactions.3.Four isotactic tetranuclear rare earth complexes were successfully synthesized by the reaction of rare-earth elements(Tb,Er,Gd,Tm)with ligand(H₂L):[Tb₄(?₃-OH)₂(HL)₂(L)₂Cl₄]·2Me OH(10),[Er₄(?₃-OH)₂(HL)₂(L)₂Cl₄]·2Me OH(11),[Gd₄(?₃-OH)₂(HL)₂(L)₂Cl₄]·2Me OH(12),[Tm₄(?₃-OH)₂(HL)₂(L)₂Cl₄]·2Me OH(13).The complexes 10-13 were characterized.The four octahedral rare earth ions in complexes 10-13 are in plane structure and there is hydrogen bond interaction between molecules.The magnetic properties of complexes 10 and 11 were further studied.The results show that the metal ions are antiferromagnetic interactions.The solid state fluorescence of complexes10-11 and the solvent recognition of complex 10 were determined.