| Recently,rational design and synthesis of metal-organic frameworks(MOF)as functional materials have attracted great attention due to their structural novelties and potential applications in gas adsorption and separation,catalysis,luminescence,electricity and magnetics.In this paper,the carboxylic acid ligand of N,N,N-(trimethylamino)tris-(1,1'-biphenyl)-2'-carboxylic acid(H3TMCA)and the hydrazide ligands of N,N-bis(4-methylene-(1,1'-biphenyl)-2'-salicylaldehyde benzoyl hydrazide)dimethylaminesalt(H2BMBD)andN,N,N-tris(4-methylene-(1,1'-biphen-yl)-2'salicylaldehyde benzoyl hydrazide)methylamine salt(H3TMBM).Based on self-assemble strategy,16 novel metal complexes were synthesized and then characterized by single crystal X-ray diffraction,powder XRD and TGA.Furthermore,the luminescent or magnetic properties of some complexes were studied.Main tasks are exhibited in the following.1.Under solvothermal condition,eight novel structures were constructed with different reaction conditions by the reaction of Zn2+,Cd2+or rare earth metal salts,based on the rich coordination mode of carboxylate groups and the semi-rigid feature of the tricarboxylic acid ligand(H3TMCA).(1){[Zn3(TMCA)2]}n(2){[Zn4(?4-O)(TMCA)2]}n(3){[Cd(HTMCA)(H2O)]·(H2O)·(DMA)}n(4){[Cd(TMCA)·(CH3CH3NH2)]·(H2O)}n(5){[Cd(TMCA)(H2O)]·(H2O)5}n(6){[Ln(TMCA)(DEF)(H2O)]}n[Ln=Eu(6),Tb(7),Gd(8)]X-ray single crystal diffraction analysis shows that complex 1 is a three-dimensional network structure in which each TMCA3-is bridged by six Zn2+ions to form a"honeycomb"structure.In complex 2,the tetranuclear units of[Zn4(?4-O)]are bridged by TMCA3-anions to form a two-dimensional layered structure.Complex 1 and 2 exhibit unique photoluminescences which are similar to those of rare earth ions.The detection of nitroaromatics shows that complex 1 is better sensitive to 4-nitrophenol.Complex 3 is a two-dimensional layered structure,while both of complexes 4 and 5 are three-dimensional network structures with different configurations.Complexes 6-8 are isomorphic with a two-dimensional layered structure.Compounds 6 and 7 have characteristic emissions of Eu3+and Tb3+,respectively.Complex 6 is explored to detect metal cations,and found that it has a better recognition ability on Fe3+ion.In addition,by adjusting the Eu/Tb ratio,a yellow luminescent material containing Eu3+/Tb3+is obtained.2.Under solvothermal conditions,by the reaction of H2BMBD with Ni(ClO4)2·6H2O,NiCl2·6H2O,Ni(CH3COO)2·4H2O and FeSO4·7H2O,respectively,four metal-organic framework compounds are constructed with different structures:(9)[Ni4(BMBD3-)2(EtOH)2(DMF)2]·(ClO4)2·(EtOH)2·(DMF)2(10)[Ni4(BMBD3-)2(Cl)2(MeOH)2]·(DMF)2(11)[Ni4(BMBD3-)2(CH3COO)2]·(H2O)4·(DMF)4(12)[Fe2(BMBD3-)2]·(H2O)6X-ray single crystal diffraction analysis shows that compounds 9,10 and 11 are all tetranuclear coordination clusters with similar structure constructed by four Ni2+ions and two ligands,except that the unsaturated coordination sites of metal ions are occupied by different solvent molecules.Complex 12 is a dinuclear coordination cluster with two Fe2+ions and two ligands.The magnetic studies show that complexes9,10,and 12 exhibit antiferromagnetic behavior,while complex 11 exhibits spin tilting magnetic behavior.3.Taking advantage of the hydrazide ligand H3TMBM which is of large steric confinement,four Zn2+-containing complexes 13,14,15 and 16 are constructed under solvothermal conditions.(13)[Zn6(TMBM)2(ClO4)(CH3OH)(CH3CN)4(H2O)]·(ClO4)7(14)[Zn12(TMBM)4(HO)6(HCOO)5(DMF)]·(H2O)8·(NO3)5·(HCOOH)-(CH3OH)2·(DMF)4(15){[Zn6(TMBM)2(HCOO)5]·(H2O)4·(NO3)3·(DMF)2}n(16){[Zn6(TMBM)2(HO)4(HCO2)(OOC-CH=CH-COO)]·(H2O)2·(DMF)3-(NO3)}nAll these four compounds have a six-nuclear tetrahedral unit[Zn6(TMBM)2].Complex 14 has two[Zn6(TMBM)2]units which are bridged by a HCOO-anion.Complex 15 and 16 are one-dimensional chains in which the[Zn6(TMBM)2]units are bridged by HCOO-and-OOC-CH=CH-COO-anions.The difference is that the unsaturated coordination sites of Zn2+ions in[Zn6(TMBM)2]unit are occupaied by different anions or solvent molecules. |
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