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1.
通过使用一个半刚性的多齿羧酸配体3,3',3"-(((2,4,6-trimethylbenzene-1,3,5-triyl)tris(methylene))tris(oxy))tribenzoic acid (H3L),在溶剂热条件下合成了4个配位聚合物{[Cd3(L)2(H2O)2]·5DMF·6H2O}n (1),{[Co3(L)2(H2O)2]·2DMF·6H2O}n (2),{[Mn3(L)2(H2O)2]·3DMF·6H2O}n (3),{[Zn3(L)2(H2O)2]·5DMA·5H2O}n (4),并通过X射线单晶衍射,热重分析对配合物结构进行了表征。4个化合物都是同构的,由沙漏型的M3簇和L3-配体作为次级结构单元,从而给出了一个金属-有机纳米笼的三维结构,从拓扑学的观点看,4个配合物的结构可以看作是三节点的(3,3,6)-连接的网络。荧光光谱测试表明配合物14在激发波长为272 nm下,在385 nm处显示了强的宽发射峰。荧光传感测试结果表明,配合物1是一种潜在的硝基苯类化合物的传感材料。  相似文献   

2.
A new quinoline-based chemosensor 1 has been designed and synthesised. Its metal ion-binding properties have been documented in organic and aqueous organic solvents. While chemosensor 1 recognises Hg2+ ions (K a = 2.15 × 104 M? 1) by exhibiting ratiometric change in emission in CHCl3/CH3OH (1:1, v/v), under similar condition both Zn2+ and Cd2+ ions are sensed by significant non-ratiometric increase in emission with measurable red shift. In DMSO/H2O (5:95, v/v), the sensor 1 exhibits a greater selectivity towards Hg2+ ions (K a = 9.20 × 103 M? 1) over the other metal ions examined.  相似文献   

3.
The complexes of Tl+, Pb2+ and Cd2+ cations with the macrocyclic ligand, dicyclohexano-18-crown-6\linebreak(DC18C6) were studied in water/methanol (H2+O/MeOH), water/1-propanol (H2+O/1-PrOH), water/acetonitrile (H2+O/AN), water/dimethylformamide (H2+O/DMF), dimethylformamide/acetonitrile (DMF/AN), dimethylformamide/methanol (DMF/MeOH), dimethylformamide/1-propanol (DMF/1-PrOH) and dimethylformamide/nitromethane (DMF/NM) mixed solvents at 22 °C using differential pulse polarography (DPP), square wave polarography and conductometry. In general, the stability of the complexes was found to decrease with increasing concentration of water in aqueous/non-aqueous mixed solvents with an inverse relationship between the stability constants of the complexes and the concentration of DMF in non-aqueous mixed solvents. The results show that the change in stability of DC18C6.Tl+, vs the composition of solvent in DMF/AN and DMF/NM mixed solvents is apparently different from that in DMF/MeOH and DMF/1-PrOH mixed solvents. While the variation of stability constants of the DC18C6.Tl+ and DC18C6.Pb2+ complexes vs the composition of H2+O/AN mixed solvents is monotonic, an anomalous behavior was observed for variations of log Kf vs the composition of H2+O/1-PrOH and H2+O/MeOH mixed solvents. The selectivity order of the DC18C6 ligand for the cations was found to be Pb2+ > Tl+ > Cd2+.  相似文献   

4.
In this work, we report a series of cyclophane fluorescent sensors based on acridine combining with imidazolium through ether linkages. X-ray crystal structures demonstrated the self-assembly behavior of these cyclophanes in the solid state driven by hydrogen bond and π–π interactions. Sensors showed excellent selectivity towards Fe3+ in aqueous solution (H2O/CH3CN?=?49:1, v/v) and H2PO4? in acetonitrile solution with notable color change under UV light, evident changes were also noticed in fluorescence spectra. In fluorescence emission, the obvious turn-off was induced by Fe3+ in aqueous solution and the obvious turn-on as well as bathochromic-shift was induced by H2PO4? in acetonitrile solution.  相似文献   

5.
6.
以2,7-萘二磺酸(2,7-H2NDA)作为结构导向剂,与五元瓜环(Q[5])和碱金属、碱土离子(K+、Rb+、Mg2+、Ca2+)在水热条件下制备出了4种新颖的Q[5]基超分子自组装体[K2(H2O)4(Q[5])](2,7-NDA)·4H2O (1)、[Rb2(H2O)5(Q[5])](2,7-NDA)·3H2O (2)、[Mg (H2O)4(Q[5])](2,7-NDA)·8H2O (3)和[Ca (H2O)4(Q[5])](2,7-NDA)·10H2O (4)。单晶X射线衍射测试结果表明,自组装体12具有相同的结构: Q[5]分子与金属离子配位形成的是“分子胶囊”;而在3中Q[5]与Mg2+配位形成的是1:1型简单配合物结构;在自组装体4中,Q[5]与Ca2+配位形成的是一维Q[5]-Ca2+配位聚合物链结构。这些结构中2,7-NDA2-阴离子平衡了体系电荷,且通过其与瓜环外壁之间的弱相互作用,促进自组装体最终构筑成三维超分子结构。此外,还研究了自组装体4的溶剂识别荧光传感性能,结果表明其能够作为有机溶剂丙酮和DMF的猝灭型荧光探针。  相似文献   

7.
A modified method of synthesis of a phosphoryl podand, 1,5-bis[2-(dihydroxyphosphinyl)phenoxy]-3-oxapentane (L), has been developed. The IR spectra of this podand and its dehydrate (L [L · H2O] · H2O (I) have been studied, the structure of I has been determined by X-ray crystallography. The crystals are orthorhombic, a = 9.4006(19) ?, b = 25.494(5) ?, c = 8.4264(17) ?, V = 2019.5(7) ?3, Z = 4, space group Pna21, R = 0.0512 for 3016 reflections with I > 2σ(I). Compound I is a host-guest molecular complex. Phosphoryl podand L acts as a host molecule, and one of the water molecules (H2O(11)) is a guest. This molecule forms one donor and one acceptor intramolecular hydrogen bond with hydroxyl groups of two phosphoryl groups (O(8)H(4) and O(3)H(2)) and combines them into an 18-membered macrocyclic ring, acting as a kind of “lock.” The H2O(11) molecule forms a second donor intramolecular hydrogen bond with the O(5) ether atom. The neutral molecular complexes are linked by hydrogen bonds directly and through the second water molecule (H2O(10)) into chains running along the c axis.  相似文献   

8.
Variations in the ratio of monomer/excimer emissions from pyrenyl groups bound to a calix[4]arene through facing carboxamidomethyl substituents have been investigated in H2O/CH3CN mixtures. Above a level of 50% H2O, monomer emission declines and the excimer emission concomitantly increases. DFT calculations support the argument that disruption of intramolecular NHO bonds by water results in a geometry, which favors contact of the pyrene units and thus a strong excimer emission. Addition of Fe(III) to a H2O/CH3CN (4:1, v/v) solution of 1 at pH 6.1 quenches both monomer and excimer emissions through electron transfer (eT) from excited pyrene to the metal ion.  相似文献   

9.
设计合成了四种三苯基咪唑类化合物:4,5-二苯基-2-对甲酰基苯基咪唑(2a),4,5-二(2-硝基苯基)-2-对甲酰基苯基咪唑(2b),N-苄基-4,5-二苯基-2-对甲酰基苯基咪唑(2c)和N-苄基-4,5-二(2-硝基苯基)-2-对甲酰基苯基咪唑(2d),并用FT-IR,NMR和MS进行结构表征.在乙酸乙酯-石油醚溶液中获得了2c的单晶,用X射线单晶衍射法测定了其晶体结构,晶体属于三斜晶系,空间群P1,晶胞参数a=0.73796(15)nm,b=0.90136(18)nm,c=1.6644(3)nm,α=86.87(3)°,β=78.25(3)°,γ=89.94(3)°,V=1.0822(4)nm3,Dc=1.272g/cm3,Z=2,F(000)=436,μ=0.077mm-1,R1=0.0459,wR2=0.1303.研究了四种化合物的紫外与荧光性质,发现官能团硝基与苄基的引入,对其吸收峰和发射峰均有不同程度的影响:在紫外光谱中两种官能团均使吸收峰蓝移;在荧光光谱中苄基使发射峰蓝移而硝基使发射峰红移.测定了2a和2c在不同溶剂中的荧光寿命,其中2a在DMSO中寿命最长,为3.18ns.这些光谱性质为研究其双光子吸收、双光子荧光和非线性光学性质奠定了理论和实验基础.  相似文献   

10.
A new gelator 1 containing triphenylamine was designed and synthesized, and formed stable gel in ethyl acetate. The self-assembly process of molecule 1 was thoroughly investigated. The solid microsphere structure formed in gel 1 could be turned into nanotube in the transition process of gel to gel via sonication. At the same time, the intermolecular hydrogen bond of self-assembly system was obviously enhanced under sonication. The XRD and water contact angle experiments results of xerogel 1 before and after sonication showed great difference. The hydrophobicity of xerogel 1 film was obviously decreased with the change of contact angle from 142° to 129° after sonication at 100 W for one minute. From the results, it was possible that the solid microsphere was re-dissolved and further reassembled into nanotube. To our knowledge, it was the first example that the solid sphere structure was changed into nanotube in self-assembly system via sonication.  相似文献   

11.
Hydrothermal reactions of Sm2O3, Gd(ClO4)3?·?6H2O and Tb(ClO4)3?·?6H2O with nitrilotriacetic acid, give rise to three lanthanide coordination polymers, {[Sm(NTA)(H2O)2]?·?H2O} n (1), {[Gd(NTA)(H2O)]?·?H2O} n (2) and {[Tb(NTA)(H2O)]?·?H2O} n (3). Their solid-state structures have been characterized by elemental analysis, and IR spectroscopy. X-ray single-crystal diffraction analyses indicated that 2 and 3 are isomorphous three-dimensional coordination polymers with eight-coordinate Gd(III) (or Tb(III)), while 1 forms a two-dimensional coordination polymer containing nine-coordinate Sm(III). The photophysical properties of 3 have been studied with excitation and emission spectra, which exhibit strong green emission.  相似文献   

12.
Three new diruthenium(III) complexes, [Ru2O(2-sb)2(2,2′-bipy)2(H2O)2]·2.5H2O (1), [Ru2O(3-sb)2(2,2′-bipy)2(H2O)2]·9H2O (2), and [Ru2O (4-sb)2(2,2′-bipy)2(H2O)2]·9H2O (3), where sb2? is sulfobenzoate dianion and 2,2′-bipy is 2,2′-bipyridine, were synthesized using hydrothermal methods and characterized by IR, elemental analysis, thermogravimetric analysis, UV–vis, and fluorescence spectra. The single crystal X-ray analysis showed that each of these complexes has a dinuclear core stabilized by two bridging carboxylates and one bridging O2?. Variable sb2? ligands (2-sb, 3-sb, and 4-sb) in these complexes lead to diverse electronic spectroscopic behavior. The efficiency of activating methyl phenyl sulfide oxidation utilizing H2O2 in 3 equiv. was studied at 23?±?2?°C. The effect of the amount of catalyst and solvents on activities was investigated. Under optimized reaction conditions, the major product was sulfoxide. Complex 1 gave significant conversion of 100 and 98% selectivity for sulfoxide after 4?h.  相似文献   

13.
Four new anthraquinone-1,5-disulfonate (L)-based metal complexes with N,N-bidentate chelating coligands, {[Pb(phen)2(L)]?·?4H2O} n (1), {[Mn2(2,2′-bipy)2(H2O)6(L)]?·?L?·?6H2O} (2), [Co(phen)2(H2O)(L)] (3), and [Zn(phen)2(H2O)(L)] (4) (phen = 1,10-phenanthroline and 2,2′-bipy?=?2,2′-bipyridine), have been hydrothermally synthesized and were structurally characterized by single-crystal X-ray diffraction, elemental analyses, FT-IR spectra, thermogravimetric curves, and solid luminescence spectra. Structural analysis suggests that 1 is a polymeric 1D zigzag chain bridged by dianionic L. In contrast, the other three complexes have discrete centrosymmetric binuclear structure for 2 and isolated isomorphic mononuclear entities for 3 and 4, which are further assembled into 3D supramolecular networks by abundant hydrogen-bonding and/or π–π stacking interactions. Additionally, 2 and 4 exhibit favorable luminescent emissions, suggesting they are potential candidates for light emission materials.  相似文献   

14.
A series of polymeric cobalt(II), nickel(II), zinc(II) and cadmium(II) azido complexes with hydrazine of the type [M(N2H4)(H2O)(N3)Cl]n, [M(N2H4)(N3)2]n and [M(N2H4)2(N3)2]n have been prepared. These were characterized by elemental analyses, magnetic susceptibility measurements, electronic and IR spectra. The complexes are highly insoluble in polar and non polar solvents. All the complexes decompose with explosion at different temperatures between 100°C to 200°C. The magnetic moment and electronic spectral data for Co(II) and Ni(II) complexes suggest that the complexes have octahedral structure. The ligand-field parameters (10 Dq, B, β, β° and LFSE) have also been calculated for all Co(II) and Ni(II) complexes which indicate a significant covalent character of M-L bonds. The IR spectra of the complexes show that the azide group and hydrazine molecule both act as bidentate bridging ligands in [M(N2H4)(H2O)(N3)Cl]n and [M(N2H4)(N3)2]n type complexes but the azide group is terminally bonded to metal in all [M(N2H4)2(N3)2]n type complexes.  相似文献   

15.
Four new substituted amino acid ligands, N-(3-hydroxybenzyl)-glycine acid (HL1), N-(3-hydroxybenzyl)-alanine acid (HL2), N-(3-hydroxybenzyl)-phenylalanine acid (HL3), and N-(3-hydroxybenzyl)-leucine acid (HL4), were synthesized and characterized on the basis of 1H NMR, IR, ESI-MS, and elemental analyses. The crystal structures of their copper(II) complexes [Cu(L1)2]·2H2O (1), [Cu(L2)2(H2O)] (2), [Cu(L3)2(CH3OH)] (3), and [Cu(L4)2(H2O)]·H2O (4) were determined by X-ray diffraction analysis. The ligands coordinate with copper(II) through secondary amine and carboxylate in all complexes. In 2, 3, and 4, additional water or methanol coordinates, completing a distorted tetragonal pyramidal coordination geometry around copper. Fluorescence titration spectra, electronic absorption titration spectra, and EB displacement indicate that all the complexes bind to CT-DNA. Intrinsic binding constants of the copper(II) complexes with CT-DNA are 1.32?×?106?M?1, 4.32?×?105?M?1, 5.00?×?105?M?1, and 5.70?×?104?M?1 for 1, 2, 3, and 4, respectively. Antioxidant activities of the compounds have been investigated by spectrophotometric measurements. The results show that the Cu(II) complexes have similar superoxide dismutase activity to that of native Cu, Zn-SOD.  相似文献   

16.
Two transition metal complexes, [Cu2(bpdc)2H2O]·2H2O (1) and Zn(bpdc)(H2O)2 (2) (H2bpdc?=?2,2′-bipyridine-6,6′-dicarboxylic acid), were synthesized and characterized by elemental analysis, IR spectroscopy, and single-crystal X-ray diffraction. Complex 1 is dinuclear with two five-coordinate cupric ions and 2 is mononuclear with one six-coordinate zinc. Interactions of 1 and 2 with DNA have been investigated using UV–Vis absorption spectra. The cleavage reaction on DNA has been monitored by agarose gel electrophoresis.  相似文献   

17.
以3,3'',5,5''-四-(羧基苯基)联苯为配体(H4L),与镧系金属Ln(Ⅲ)盐反应,自组装形成了5个具有三维孔洞结构的镧系金属-有机框架材料:{[Ln3L2(H2O)7]·(OH)·10DMA}n(Ln=Gd (1a); Ln=Ho(2a), {[Ln3L2(H2O)3]·(OH)·mDMA}n (Ln=Er,m=10(1b); Ln=Yb, m=9(2b); Ln=Lu, m=10(3b))。单晶X射线衍射分析表明,这些MOFs属于2种系列的类质同晶化合物,分别属于正交晶系Ccca空间群和单斜晶系C2/c空间群。有机小分子溶剂交换荧光研究发现,2b对小分子二氯甲烷和甲苯荧光有增强效应,表现出良好的荧光探测功能。  相似文献   

18.
Kinetic study on the cleavage of N‐(4′‐methoxyphenyl)phthalamic acid (NMPPAH) in mixed H2O‐CH3CN and H2O‐1,4‐dioxan solvents containing 0.05 M HCl reveals the formation of phthalic anhydride (PAn)/phthalic acid (PA) as the sole or major product. Pseudo first‐order rate constants (k1) for the conversion of NMPPAH to PAn decrease nonlinearly from 60.4 × 10?5 to 2.64 × 10?5 s?1 with the increase in the contents of 1,4‐dioxan from 10 to 80% v/v in mixed aqueous solvents. The rate of cleavage of NMPPAH in mixed H2O‐CH3CN solvents at ≥50% v/v CH3CN follows an irreversible consecutive reaction path: NMPPAH PA. The values of k1 are larger in H2O‐CH3CN than in H2O‐1,4‐dioxan solvents. © 2004 Wiley Periodicals, Inc. Int J Chem Kinet 36: 316–325, 2004  相似文献   

19.
Self-assembly of 4-aminoantipyrine (AAP) and 5-nitroisophthalic acid (H2NIP) with Co(CH3COO)2 or Cd(NO3)2 in CH3OH–H2O at room temperature generated {[Co2(AAP)(NIP)(H2O)8][Co(AAP)(NIP)2(H2O)2](H2O)4.5} (1) and {[Cd(AAP)(NIP)(H2O)](H2O)} n (2), which were further characterized by X-ray diffraction, IR spectra, elemental analysis and solid-state fluorescence spectra. The structure analysis indicates that 1 contains two individual fragments, one NIP-bridged six-coordinate binuclear CoII cation and a mononuclear CoII dianion. The binuclear units are connected into 1-D chains via O–H?···?O hydrogen bond interactions, which were further assembled into a 2-D supramolecular layer bridged by the mononuclear CoII unit. Complex 2 is a linear NIP bridged seven-coordinate CdII polymeric chain with the terminal AAP ligands as decorations, and are further extended into 2-D network by classic hydrogen bonds and π?···?π stacking interactions. Both solid complexes exhibit emission spectra from intraligand electron transfer at room temperature.  相似文献   

20.
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