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1.
Ionothermal reaction between Ni2+ and 1,3,5-benzentricarboxylic acid (H3BTC) with [AMI]Cl (AMI=1-amyl-3-methylimidazolium) as the reaction medium produced a novel 3D mixed-ligand metal-organic framework [AMI][Ni3(BTC)2(OAc)(MI)3] (1) (MI=1-methylimidazole) with [AMI]+ incorporated in the framework. The framework is formed by connecting 2D planes, made up of 32- and 48-membered rings, through 1D chains composed of 32-membered rings. The two BTC3− ligands in 1 show the same connectivity mode with two bidentate and one μ2 bridging carboxylic groups. This is a new connectivity mode to the already existing 17 in the Ni-BTC system. The role of MI and [AMI]Cl in the structure formation is discussed.  相似文献   

2.
《Electroanalysis》2017,29(12):2810-2817
In this study, the synthesis and characterization of a Cu‐based metal‐organic framework (MOF) [Cu3(BTC)2(H2O)3]n (where BTC=benzene‐1,3,5‐tricarboxylate), known as HKUST‐1, were performed. The Cu‐MOF was applied in the modification of a carbon paste to obtain a biomimetic sensor for the electrochemical determination of catechol. Kinetic assays confirmed that the Cu‐MOF acts as a catalyst for the oxidation of catechol and it can be considered as a catechol oxidase mimetic. Under optimized conditions, the calibration curve for catechol presented a linear range of 8.0×10−7 to 3.2×10−5 mol L−1, with detection limit of=1.0×10−7 mol L−1. The sensor demonstrated good intra‐day repeatability and inter‐electrode reproducibility (relative standard deviations of 3.8 % (n=10) and 4.3 % (n=6), respectively). In the selectivity study, an adequate peak‐to‐peak separation was observed for hydroquinone and uric acid in relation to catechol, demonstrating that this sensor has the potential for use in the simultaneous determination of these compounds. This sensor was successfully applied in the determination of catechol in water samples.  相似文献   

3.
The ZnII‐CoII organic framework [Me2NH2][Zn2Co(μ3‐OH)(BTC)2(H2O)] · 2H2O ( FJI‐6 ) (H3BTC = 1, 3,5‐benzenetricarboxylic acid and DMA = N.N′‐dimethyl acetamide), was synthesized and structurally characterized. FJI‐6 shows a three‐dimensional heterometallic microporous framework with coexisting octahedral cages and one‐dimensional channels assembled by Zn2Co(μ3‐OH)(CO2)6 secondary building units. In addition, the sorption behavior and magnetic properties of FJI‐6 were investigated.  相似文献   

4.
Two heterometallic cluster compounds and one monometallic cluster compound, namely [Ni9Co6(PMIDA)6(BTC)2(H2O)12]·6H2O (1), [Co13Zn2(PMIDA)6(H2O)18]·6NO3·15H2O (2), and [Fe15(PMIDA)6(BTC)2(H2O)22]·38H2O (3), have been obtained under hydrothermal conditions using N-(phosphonomethyl)imino-diacetic acid (H4PMIDA) and 1,3,5-benzenetricarboxylate acid (H3BTC) as ligands, and structurally characterized by X-ray crystallography. Compound 1 exhibits a 3D open framework constructed from [Ni9Co6(PMIDA)6(H2O)12]6+ heteronuclear clusters and BTC3? ligands. Compounds 2 and 3 are both zero-dimensional polynuclear clusters, further extended into 3D supramolecular structures via hydrogen-bonding interactions. However, there are some differences in their crystal structures; compound 2 features an isolated spherical heteronuclear cation cluster based on PMIDA4? ligands, such that the NO3 ? anions only balance the charge, whereas compound 3 is characterized as a neutral monometallic cluster incorporating two different types of organic acid ligands, namely PMIDA4? and BTC3?, and the two BTC3? ligands exhibit regular distribution in each cluster. The luminescence properties of all three compounds have been investigated at room temperature.  相似文献   

5.
A rare porous metal-phosphonocarboxylate framework with ultrahigh thermal stability over 500℃ was obtained, which can be transformed into three different cluster-based frameworks with the same CaF2-type topology.  相似文献   

6.
Two new copper(II) complexes, [Cu(tacn)(H2BTC)2]·2H2O (1) and [Cu(tacn)(H2BTC)(H2O)](H2BTC)·5H2O (2), where H2BTC = the benzene-1,3,5-tricarboxylic acid anion and tacn =1,4,7-triazacyclononane, have been synthesized and their structures determined. Copper(II) ions of both (1) and (2) are five-coordinate with three nitrogen atoms of tacn and two oxygen atoms of either H2BTC or H2O. Hydrogen bonds in these two complexes result in them being differently packed in the crystal cell.  相似文献   

7.
A solvothermal reaction of Zn(NO3)2 ? 6 H2O, tetra‐(4‐pyridyl)porphyrin (H2TPyP), and 4,4′‐oxybis(benzoic acid) (H2OBA) resulted in a new two‐dimensional Zn‐ porphyrin metal–organic framework compound, [Zn2(C40H24N8)0.5(C14H8O5)(DMA)](DMA)(H2O)6 ( 1 ; DMA=N,N‐dimethylacetamide). The ZnII ions present in 1 could be exchanged by using a solution of Cu(NO3)2 ? 3 H2O in DMA at room temperature to give [Cu2(C40H24N8)0.5(C14H8O5)(DMA)](DMA)(H2O)3 ( Cu1 ). The extra‐framework solvent molecules have been shown to be reversibly removed or exchanged without collapse of the framework. Solvent‐free Cu1 was explored as an active heterogeneous catalyst towards three different organic reactions: 1) the chemical fixation of CO2 into cyclic carbonate at room temperature and 1 atm; 2) the nitroaldol reaction under solvent‐free conditions, and 3) the three‐component coupling of aminopyridine, benzaldehyde, and aryl alkynes followed by 5‐exo‐dig cyclization to produce the important pharmacophore imidazopyridine.  相似文献   

8.
A new magnetic metal–organic framework (MOF), namely, NiFe2O4@SiO2@Cu3(BTC)2, was synthesized via an in situ method using Fe(NO3)3, Ni(NO3)2, CuN2O6, TEOS, (3-aminopropyl)triethoxysilane, and benzene-1,3,5-tricarboxylic acid. Three different samples were fabricated according to a formula; xNiFe2O4@(100 − x)SiO2@Cu3(BTC)2, where x = 10, 30, and 50. The integration of the intrinsic characteristic of Cu3(BTC)2 as an MOF with strong magnetic properties of NiFe2O4 could lead to an exquisite material with specific behaviors. X-ray diffraction (XRD), Fourier transform infrared (FTIR), scanning electron microscopy (SEM), Brunauer–Emmett–Teller (BET), diffuse reflectance spectroscopy (DRS), photoluminescence (PL), vibrating sample magnetometer (VSM), transmission electron microscopy (TEM), and simulated thermal analyzer (STA) were utilized to characterize the mentioned samples. Results approved that the synthesized compounds were composed of SiO2 and Cu-MOF and NiFe2O4 crystalline phases with rod-like morphology. The similarity between the morphology of the synthesized samples and Cu-MOF approved that an appropriate fabrication method has been selected. This fact led to observe mesoporous composites with 38–90 m2 g−1 specific surface area. PL spectroscopy confirmed the near bandgap emission, ligand-to-metal charge transfer, and metal-to-ligand charge transfer. Although all the samples had magnetic hysteresis, the highest magnetization was seen in the 50NiFe2O4@SiO2@Cu3(BTC)2 sample. This composite compound with a magnetization value of 2 emu g−1 at 8000 Oe and a specific surface area of 90 m2 g−1 could be classified as a magnetic MOF (MMOF). STA results suggested that 400°C is the highest operating temperature for this compound.  相似文献   

9.
A new dioxime ligand, N,N-bis(2-{[(2,2-dimethyl-1,3-dioxolan-4-yl)methyl]amino} ethyl)N′,N′-dihydroxyethanediimidamide (H2L), and its mononuclear complexes with Co2+, Ni2+, Cu2+, Zn2+ and Cd2+ are synthesized. H2L forms transition metal complexes [Co(LH)2(H2O)2] and [M(LH)2] (M = Ni2+, Cu2+) with a metal : ligand ratio of 1 : 2. Complexes [M(H2L)(Cl)2] (Zn2+, Cd2+) have a metal : ligand ratio of 1 : 1. The mononuclear Co2+, Ni2+, and Cu2+ complexes indicate that the metal ions coordinate ligand through its two N atoms, as the most of dioximes. In the Co2+ complex, two water molecules and in the Zn2+ and Cd2+ complexes two chloride ions are also coordinated to the metal ion. The structures of these compounds are identified by elemental analyses, IR, 1H and 13C NMR, electronic spectra, magnetic susceptibility measurements, conductivity, and thermogravimetric analysis.__________From Koordinatsionnaya Khimiya, Vol. 31, No. 7, 2005, pp. 540–544.Original English Text Copyright © 2005 by Canpolat, Kaya.The text was submitted by the authors in English.  相似文献   

10.
Six mononuclear complexes are reported with the tetradentate ligand N,N′-bis(2-pyridylmethyl)-1,3-propanediamine, (abbreviated as pypn) i.e. [Cu(pypn)(ClO4)2](H2O)1/2 (1), [Fe(pypn)Cl2](NO3) (2), [Zn(pypn)Cl](ClO4) (3), [Co(pypn)(NCS)2](ClO4) (4), [Co(pypn)(N3)2](ClO4) (5), [Zn(pypn)(NCS)2] (6). The synthesis and X-ray crystal structures of all six compounds and their spectroscopic properties are presented.The geometry of the Cu2+, Co3+, Zn2+, Fe3+ ions is essentially octahedrally based, with the mm conformation (for Cu) and msf conformations for the other 3 metal ions; in compound 3 the geometry around the Zn2+ is distorted trigonal bipyramidal. The stabilisation of the crystal lattices is maintained by interesting, relative strong hydrogen bonds.  相似文献   

11.
Two coordination polymers based on 1, 6‐bis(2‐methyl‐imidazole‐1‐yl)‐hexane (bimh), namely {[Zn3(BTC)2(bimh)] · (bimh)}n ( 1 ) and {[Zn(IPA)(bimh)] · (CH3CH2OH)0.5}n ( 2 ) (H3BTC = trimesic acid, H2IPA = isophthalic acid), were synthesized through hydrothermal reactions. In compound 1 , the zinc(II) ions are bridged by BTC3– ligands to form an undulating infinite two‐dimensional (2D) polymeric network. The 3D networks of 1 show a twofold interpenetrating net. In compound 2 , zinc(II) ions are bridged by IPA2– ligands to form one‐dimensional (1D) helical structures. The 2D structures of 2 are further assembled into 3D networks through aromatic π–π stacking interactions. Both compounds exhibit strong photoluminescence at room temperature and may be good candidates for potential luminescence materials.  相似文献   

12.
CoII and CoIII complexes containing nitrite and tridentate aromatic amine compounds [bis(6-methyl-2-pyridylmethyl)amine (Me2bpa) and bis(2-pyridylmethyl)amine (bpa)] have been prepared as models of the catalytic center in Co-substituted nitrite reductase: [CoII(Me2bpa)(NO2)Cl]2 · acetone (2), CoII(Me2bpa)(NO2)2 (3), CoII(bpa)(NO2)Cl (4), CoII(bpa)(NO2)2 (5), CoIII(Me2bpa)(NO2)(CO3) (6), and CoIII(bpa)(NO2)3 (7). The X-ray crystal structure analyses of these CoII and CoIII complexes indicated that the geometries of the cobalt centers are distorted octahedral and the Me2bpa and bpa with three nitrogen donors exhibit mer- (2, 3, and 7) and fac-form (4 and 6). The coordination mode of nitrite depends on the cobalt oxidation state, to CoII through the oxygen (nitrito coordination, O- and O,O-coordination) and to CoIII through nitrogen (nitro coordination, N-coordination mode). These findings are consistent with the results of their IR spectra, except that another oxygen of the O-coordinated nitrito group in 3 might interact weakly with CoII according to its IR spectrum. Reductions of the nitrite in 2, 3, 4, and 5 to nitrogen monoxide were not accelerated in the presence of proton, perhaps due to the nitrito coordination in these CoII complexes.  相似文献   

13.
Systematic access to metal‐functionalized polyoxometalates has thus far been limited to lacunary tungsten oxide and molybdenum oxide clusters. The first controlled, stepwise bottom‐up assembly route to metal‐functionalized molecular vanadium oxides is now presented. A di‐vacant vanadate cluster with two metal binding sites, (DMA)2[V12O32Cl]3? (DMA=dimethylammonium) is formed spontaneously in solution and characterized by single‐crystal X‐ray diffraction, ESI mass spectrometry, 51V NMR spectroscopy, and elemental analyses. In the cluster, the metal binding sites are selectively blocked by hydrogen‐bonded DMA placeholder cations. Reaction of the cluster with transition metals TM (Fe3+, Co2+, Cu2+, Zn2+) gives access to mono‐functionalized vanadate clusters (DMA)[{TM(L)}V12O32Cl]n? (L=ligand). Metal binding is accomplished by significant distortions of the vanadium oxide framework reminiscent of a pincer movement. Cluster stability under technologically relevant conditions in the solid‐state and solution is demonstrated.  相似文献   

14.
An effective method was developed for the synthesis of three cluster‐based frameworks with multifarious secondary building units (SBUs) and various structures, which were formulated as [Me2NH2]2[Zn10(BTC)63‐O)(μ4‐O)(H2O)5] · 3DMA · 9H2O ( FJI ‐ 3 ), [Me2NH2]2[Zn93‐OH)2(BTC)6(H2O)3] · 5DMA · 6H2O ( FJI ‐ 4 ) and [Me2NH2][Zn33‐OH)(BTC)2DMF] · H2O ( FJI ‐ 5 ) (H3BTC = 1,3,5‐benzenetricarboxylic acid, DMA = N,N′‐dimethyl acetamide and DMF = N,N′‐dimethyl formamide), respectively. X‐ray structural analysis reveals that FJI ‐ 3 displays 3D highly porous metal‐organic framework with four kinds of microporous cages constructed by two paddle‐wheel Zn2(CO2)4, trimeric Zn3O(CO2)6, and tetrameric Zn4O(CO2)6 SBUs. FJI ‐ 4 exhibits 3D microporous MOFs with a dodecahedral cavities built by paddle‐wheel Zn2(CO2)4 and trimeric Zn3O(CO2)6. FJI ‐ 5 shows 3D microporous MOFs with an 1D channel assembled by the Zn3O(CO2)6 SBUs. In addition, the fluorescence and sorption properties in these cluster‐based frameworks were also investigated. Furthermore, the method employed in this work may provide an useful approach to the design and synthesis of novel cluster‐based frameworks.  相似文献   

15.
Reactions of Cd(NO3)2 · 4H2O with 2‐quinolinecarboxylic acid (H‐QLC) in the presence of 1,4‐benzenedicarboxylic acid (H2‐BDC) or 1,3,5‐benzenetricarboxylic acid (H‐BTC) in DMF/H2O solvent afforded two compounds, namely, [Cd(QLC)(BDC)1/2(H2O)]n ( 1 ) and [Cd(QLC)(BTC)1/3]n ( 2 ). Both compounds are two‐dimensional (2D) frameworks but feature different cadmium‐carboxylate clusters as a result of the presence of the polycarboxylate ligands with different geometries and coordination preference. The dinuclear Cd2(QLC)2 units in 1 are bridged by the pairs of bridging water ligands to give a one‐dimensional (1D) chain, which is further linked by the second ligand of BDC2– to form a 2D structure. Compound 2 is constructed from unique hexanuclear macrometallacyclic Cd6(QLC)6 clusters, which are linked by the surrounding BTC3– ligands to generate a 2D structure. Photoluminescence studies showed both compounds exhibit ligand‐centered luminescent emissions with emission maxima at 405 and 401 nm, respectively.  相似文献   

16.
Complexes of the type [M(tren)(abpt)](NO3)2(H2O)n (1–6) [M = MnII, FeII, CoII, CuII, ZnII (n = 2), NiII (n = 2.25), tren = tris(2-aminoethyl)amine, and abpt = 4-amino-3,5-bis(pyridin-2yl)-1,2,4 triazole] have been prepared. The bonding mode and overall geometry of the complexes have been deduced by elemental analyses, molar conductance values, spectral studies (obtained from FT-IR), 1H-n.m.r., electronic spectral analyses and magnetic susceptibility measurements. A detailed molecular structure of complex (4) has been determined by single X-ray crystallography.  相似文献   

17.
Through ligand modification, we have replaced the central benzene ring of H2TDBA ([1,1′:3′,1″-terphenyl]-4,4″-dicarboxylic acid) with the pyridine structurally related ligand H2PDDA (4,4′-(pyridine-2,6-diyl)dibenzoic acid), which makes the central pyridine ring of H2PDDA more coplanar with two benzene rings on both sides of the ligand. The modification results in a dramatically different linkage configuration, thereby allowing structural changes to the metal-organic frameworks (MOFs). Two 2-D MOFs, [Cu(TDBA)(DMA)2]·H2O (BUT-221, DMA = N,N-dimethylacetamide), and [Cu3(PDDA)3(DMA)2(H2O)]·5H2O (BUT-223) have been synthesized through reactions of two ditopic carboxylate ligands with Cu(NO3)2·3H2O under solvothermal conditions, and characterized by single-crystal X-ray diffraction, powder X-ray diffraction, thermogravimetric analysis and infrared spectroscopy. Topological analysis shows that BUT-221 is a twofold parallel interpenetrating 44 2-D network with a skl topology, while BUT-223 is a 2-D network with a kgm topology.  相似文献   

18.
Two new 3D heterometallic frameworks, [Me2NH2][CaCd2(BTC)(HBTC)2] · 4H2O ( 1 ) and [Ba11Co2(BTC)83‐OH)22‐H2O)6(H2O)16] ( 2 ) (H3BTC = 1,3,5‐benzenetricarboxylic acid, Me2NH2 = protonated dimethylamine), were synthesized using solvothermal and hydrothermal techniques, respectively. Complex 1 features a 3D microporous framework; it contains hourglass‐like trinuclear [CaCd2(COO)6] clusters that are bridged by –COO groups and form zigzag chains. These chains are further interlinked by the –COO groups of BTC3– ligands into 2D layers with interesting flower‐like configuration, which, in turn, are connected by HBTC2– ligands to afford the 3D structure. Me2NH2+ cations not only balance the negative charges of the host framework but also play template roles to fill in the channels, further consolidating the whole framework. The complicated 3D network of complex 2 is constructed by the interconnection of 2D layers, which, in turn, are made of the infinite inorganic chains based on hexanuclear [Ba6] clusters, and these 1D chains are decorated by {CoO6} octahedrons. Interestingly, the 2D layer can be viewed as a unique structure composed of two different kinds of heart‐shaped rings, which partially overlapped in apical positions to produce a ten‐membered ring window. Moreover, the luminescence properties of 1 – 2 and the gas adsorption property of 1 have also been studied.  相似文献   

19.
The coordinating properties of a new bis(pyridylhydrazone) ligand derived from iminodiacetic acid diethyl ester and 2-pyridinecarboxaldehyde (picolinaldehyde) H3Imdp and of the bis(salicylhydrazone) H5Imds and H4MeImds ligands derived, respectively, from iminodiacetic acid diethyl ester and from methyl-iminodiacetic acid diethyl ester and salicylaldehyde were considered, by means of analytical and spectroscopic methods, towards first row transition metal ions. These ligands showed various coordination modes in complexation with Cu(II), Co(II), Mn(II) and Zn(II) ions. In particular, we have synthesized and characterized, by analytical, 1H NMR and IR techniques, tri-, di- and mononuclear metal complexes of formula Co3(HImdp)(NO3)4·2H2O, Cu3(HImdp)(NO3)4·C2H5OH·H2O, Cu3(HImdp)Cl4, Zn2(H3Imdp)(ClO4)4·2H2O, Co3(HImds)Cl2·CH3OH·H2O, Zn2(H3Imds)Cl2·2H2O, Co(H4Imds)NO3·2H2O, Mn(H4Imds)Cl·CH3OH·H2O, Cu(H3Imds)·CH3OH·H2O and Cu(H2MeImds).CH3OH·3H2O. Antibacterial, antifungal and antiprotozoal properties of H5Imds and H3Imdp together with three copper(II) trinuclear species of H5Imds of formula Cu3(HImds)(NO3)2.2CH3OH·2H2O, Cu3(HImds)(ClO4)2.EtOH·2H2O and Cu3(HImds)SO4·4H2O are also discussed. The H5Imds ligand and their trinuclear copper(II) complexes showed good activities versus Trichomonas vaginalis, Staphylococcus epidermidis and Acanthamoeba castellanii.  相似文献   

20.
合成了一系列具有高热稳定性的金属有机骨架材料RE(BTC)(H2O),(RE=Y,Tb,Eu,Yx-Tb1-x,Yx-Eu1-x),除去端基水分子后可得到具有一维孔道的空旷结构RE(BTC)。其中,Y(BTC)具有良好的氢气以及甲烷储存性能。在77 K,1 atm条件下,氢气的吸附量高达1.73wt%;在室温,4 MPa条件下,Y(BTC)的甲烷储存量达到饱和,可以达到97.7 cm3.g-1(STP),在美国能源部规定的安全储运压力(3.5 MPa)下,甲烷储存量也能达到96.0 cm3.g-1(STP),与其它同类多孔材料相比具有一定的优越性。骨架中掺杂了微量金属铽(Tb),铕(Eu)的Tbx-Y1-x(BTC)(H2O),Euy-Y1-y(BTC)(H2O)与单一金属的Tb(BTC)(H2O)和Eu(BTC)(H2O)相比,不但降低了材料的成本,而且减小了浓度淬灭对材料荧光性质的影响,优化了材料的荧光性能。  相似文献   

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