Synthesis And Properties Of Metal Complexes Based On Multi-N Azole And Polycarboxylate Ligands

The design and construction of multifunctional metal-organic frameworks(MOFs)have been a frontier for material research due to their fundamental interests,such as porosity,magnetism,catalysis,chirality,optical activity,conductivity,or ferroelectricity and their potential applications.Among them,porous coordination polymers(PCPs)have potential applications in multi-phase catalysis,host-guest molecular recognition and/or exchange,gas storage etc because of their significant characteristic features,such as high surface area,highly regular channel structures and controllable pore size approximating molecular dimensions;and PCPs with magnetism and/or chirality have given more attention for their special function in high selective separation,second-order non-linear optic(NLO)and magnetic modulation.In this dissertation,we have designed a series of novel organic ligands including triazolyl and carboxylate groups.The series of ligands have bifunctional groups and exhibited flexible coordination abilities,benifiting to construct novel metal-organic frameworks.In addition to this,we designed another novel 1-(4-(1H-imidazol-5-yl)benzene)-1H-1,2,4-triazole organic compound including multi-N donor atoms.And the ligand has good complementarity,and facilitated to build diverse frameworks.The main ligands were shown as following:In chapter 2,we have designed a series of multi-carboxyl groups bearing parent triazole,which possess good coordination abilities due to N-donor triazole and carboxyl groups.Particularly,the ligands may have good hydrophilia and may interact with biomolecules.We use these ligands to react with metal ions and obtained four metal-organic frameworks,[Cd(TZ2424)]·H2O(1),[Zn2(TZ244-4)]·(DMF)·2H2O(2),[Cd3(TZ444)2(pbda)2]·2DMF·2H2O(3)?[Cd2(TZ33)2(H2O)2]·2H2O(4).The TZ24244-ligand in complex 1 act as a ?4-bridge to connect four Cd(II)atoms in?1-?0:?1-mono-dentate and ?2-?1:?1-bis-monodentate coordination modes to form two-dimensional layer.In 2,the triazole together with three carboxyl groups link Zn(II)atoms to form two-dimensional(2D)layer,which are further to connected to three-dimensional framework.In 3,the triazole together with lateral two carboxyl groups coordinated with Cd(?)atoms to form 2D layer,and form to three-dimensional(3D)framework by the third carboxyl group.In 4,the carboxyl group from TZ332-ligands connect Cd(?)atom to form one-dimentinal chains in?1-?1:?1-and,?2-?1:?2-coordination modes.Complex 1 has good luminescent property and shows selective sensing for Fe3+.More interestingly,complex 1 exhibits interaction with bovine serum albuminIn chapter 3,five new metal-organic frameworks[Zn3(HL)2(btc)2(H2O)2]·H2O(5),[Mn(H2L)(btc)(H2O)](6),[Zn2(L)(HL)(SIP)(H2O)]4H2O(7),[Cd(H2L)(SIP)(H2 O)]·3H2O(8)and(Cd(L)(frda)(H2O)]·0.5L·H2O(9)were obtained by reactions of the different metal(?)salts with mixed ligands including 1,2,3-benzenetricarboxylic acid(H3btc),sodium 5-sulfoisophthalate(NaH2SIP)and 1-(4-(1H-imidazol-5-yl)phenyl)-1H-1,2,4-triazole(HL),respectively.All compounds were characterized by single-crystal X-ray diffraction,FT-IR spectroscopy,and elemental analysis.The study shows that the natures of organic ligands as well as metal ions play key roles in modulating the resulting frameworks of 5-8.The complex 5 is a(3,4,4)-connected 3D net with the point(Schlafli)symbol of(42·63·8)4(64·8·10),while 6 is a 2D layer structure referred as fes net with a Point(Schlafli)symbol of(4·82).Complex 7 has 2-nodal(3,3,4)-connected rare tfc net with a Point(Schlafli)symbol of(83)2(85·10),while 8 is a supramolecular polymer constructed from infinite one-dimensional(1D)chains by the interaction of rich hydrogen bonds and ?-? stacking.The luminescent properties have been investigated for the compounds 5,7,and 8 containing metal d10 Zn(?)and Cd(?)atoms.In 9,both of multi-N donor and O-donor frda2-ligands act as linear two-connectors to bridge Cd(?)atoms,forming 2D layer.Interestingly,the parallel 2D layers are stacking in an AAA…node,and the infinite 1D channels are formed along a-axis direction,where the uncoordinated L molecules are embedded in the void.Furthermore,the weak interactions including the rich hydrogen bonding and ?-? stacking interactions progress the 2D structure into 3D supramolecular polymer.Diffuse reflectance spectra and luminescent property have also been investigated.In chapter 4,another four new metal-organic frameworks(MOFs)of[Cd2(L)2(mmpa)2]·4H2O(10),[Mn2(L)2(mmpa)2]·L·2H2O(11),[Zn(L)(No2mbda)]·H2O(12),and[Cu(L)(NO2mbda)](13)were prepared by reactions of the corresponding metal(?)salts with multi-N donor 1-(4-(1H-imidazol-5-yl)phenyl)-1H-1,2,4-triazole(L)ligand and auxiliary O-donor carboxylic acids of 5-methylisophthalic acid(H2mmpa),5-nitroisophthalic acid(H2NO2mbda),respectively.The structures of MOFs 10-13 were characterized by single-crystal X-ray diffraction,elemental analysis,and FT-IR spectroscopy.MOF 10 is a binodal(4,4)-connected 3D framework with CdSO4 topology with Schlafli symbol(65·8)based on binuclear Cd2(mmpa2-)2 secondary building unit(SBU),while 11 is a uninodal 6-connected pcu alpha-Po net with a Point(Schlafli)symbol(412·63)based on[Mn2(CO2)4]SBU.Compound 12 is a 2D?3D "polycatenated network"because of their mutual interpenetration between 2D corrugated(4,4)layers,while 13 is a 2D network with(4,4)sql topology by taking the binuclear SBUs as 4-connecting nodes.UV-visible spectra and photoluminescent property together with quantum yield(QY)and luminescence lifetime were carried out for the corresponding MOFs.Microporous MOF 10 can sense nitroaromatic compounds by fluorescence quenching and show rare luminescent sense property for Ag+ion in H2O solution with high sensitivity of 1.4×10-6 M.Moreover,the activated microporous sample 10 shows selective CO2 uptake with 66.72 cm3/g,and H2O vapor adsorption as well.