| This paper includes three parts.Firstly,we synthesized five carboxylic acid ligands.Secondly,we use these five ligands to react with different transition metal ions to constructed thirteen coordination polymers through hydrothermal conditions.Their syntheses,crystal structures were investigated and discussed in detail.Finally,according to the structural difference of the coordination polymer,we have studied their applications.In addition,we successfully controlled the growth of the crystal by changing the synthetic conditions.1.Synthesis of carboxylic ligands.We have designed and synthesized five carboxylic acid ligands:2,5-di(pyridin-4-yl)terephthalic acid(L1);2'-hydroxy-[1,1':3',1 "-terphenyl]-4,4",5'-tricarboxylic acid(L2);5',5"-bis(4-carboxyphenyl)-4",6'-dimethoxy-[1,1':3,1":3",1'"-quatcrphenyl]-4,4'",-dicarboxylic acid(L3);5',5"-bis(4-carboxyphenyl)-4",6'-bis(hexyloxy)-[1,1':3',1":3",1'"-quaterphenyl]-4,4'"-dicarboxylic acid(L4);4",6'-bis((4-(tert-butyl)benzyl)oxy)-5',5"-bis(4-carboxyphenyl)-[1,1'3',1":3",1'"-quater phenyl]-4,4'"-dicarboxylic acid(L5)?2.Synthesis of coordination polymers and their characterization(1)Two lanthanide metal-organic frameworks(Ln-MOFs)with similar structures have been synthesized through objective synthesis,namely,{[Eu(L)(BPDC)1/2(NO3)]·H3O}n(1)and {[Tb(L)(BPDC)1/2(NO3)]·H3O}n(2).Two compounds are both two-fold interpenetrating 3D frameworks.Topological analyses reveal that complexes 1 and 2 are 6-connected pcu net.(2)Three coordination polymers with the same connection mode were synthesized under the solvothermal conditions by using carboxylic acid ligands L3,L4,L5 and 4,4'-bipyridine(BPY)and transition metal Zn(?),they are[Zn(L3)0.5(BPY)]n(3),[Zn(L3)0.5(BPY)]n(4),[Zn(L3)0.5(BPY)]n(5)?Among them,complex 7 is a 4-fold structure,while complexes 8 and 9 are 2-fold structure.[Cd(L)1/2(DMA)(H2O)]n(6)was synthesized under the solvothermal conditions by using ligand L3and transition metal Zn(II).Complex 6 is sql network with 2-dimensiona layered structure stacking in an AAA…mode.(3)Three Co(?)coordination polymers have been built by "Y"-shaped carboxylic acid ligands and 4,4'-di(1H-imidazol-l-yl)-1,1'-biphenyl(BIBP)and BPY ligands,namely,[Co(L)]n(7),{[Co(L)(BIBP)]-H2O}n(8),{[Co3(L)(BPY)1.5]-H2O}n(9).7 and 8 are 3-dimensional network while 9 is a 2-dimensional stucture with sql topology.(4)Four different Co(?)coordination polymers have been built by two flexible ligands 4,4'-dicarboxydiphenyl sulfone(4,4'-sdb)and 1,4-bis((1H-imidazol-1-yl)methyl)benzene(BMB)in a one-pot solvothermal reaction.The crystal structures of 1-3 were obtained,namely,[Co(4,4'-sdb)(BMB)]n(10);{[Co2(4,4'-sdb)2(BMB)]·2H2O}n(11),[Co3(4,4'-sdb)2(DMF)(H20)3]n(12),but 13 was confirmed by PXRD.The structures of 10 and 11 are new,12 and 13 have been reported.Both 1 and 2 are 2D layered structure with sql topology and their point symbol is {44·62}.3.The application of coordination polymers and their controlled synthesis.(1)We studied the fluorescence properties of complexes 1 and 2.Both the two structures were embedded in uncoordinated nitorgen atoms.As the uncoordinated pyridine groups can be used as functional groups,we tested their sening ability towards metal ions and small organic molecules.(2)By increasing the steric hindrance of substituents of L3 ligand,we successfully controlled of the interpenetration of complexes 6,7 and 8.We also investigated the application of complex 6 in the detection of small molecules(3)7 has uncoordinated oxygen atoms in carboxyl groups,and 8 owns uncoordinated carboxyl groups while 9 is totally coordinated.Here,we selected two kinds of anionic dyes,Congo red(CR)and methyl orange(MO)to investigate whether the uncoordinated functional groups can affect the adsorption capacity.(4)Based on the significant differences of the crystals structures of 10-13,we adopt solvents to regulate,finally,four kinds of pure crystals have been obtained,respectively. |
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