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1.
Two new coordination polymers [Cd(1,2‐BDC‐F4)(H2O)2(py)]n ( 1 ) and {[Cd(1,2‐BDC‐F4)(H2O)2](DMF)}n ( 2 ) were prepared from the vapor diffusion reactions of CdII acetate with tetrafluorophthalic acid (1,2‐H2BDC‐F4) under different solvent atmospheres, and structurally characterized by single‐crystal diffraction technique. Both complexes reveal polymeric coordination architectures. Complex 1 is a one‐dimensional (1D) double chain, which crystallizes in the space group, P212121. In 1 , each CdII ion is hexacoordinate by five oxygen atoms from two terminal water and three 1,2‐BDC‐F4 anions with a μ3‐bridging mode, as well as one nitrogen donor from one pyridine molecule. Complex 2 is a two‐dimensional (2D) layered network, which crystallizes in the P\bar{1} space group. In 2 , each CdII ion is heptacoordinate by seven oxygen atoms from two terminal water and four 1,2‐BDC‐F4 anions with a μ4‐bridging mode. The results clearly suggest that the judicious choice of solvent systems does play a critical role in the construction of coordination frameworks with distinct dimensionality and connectivity. Their spectroscopic, thermal, and fluorescence properties have also been investigated.  相似文献   

2.
ZnII and CdII coordination polymers with dicarboxylate and imidazole‐containing ligands, namely, [Cd (2,3‐PDC)(L)]n ( 1 ) and {[Zn(3,4‐PDC) (L)0.5] · H2O}n ( 2 ), [2,3‐H2PDC = 2,3‐pyridine dicarboxylate, 3,4‐H2PDC = 3,4‐pyridine dicarboxylate, and L = 1,4‐bis(2‐methylimidazol‐3‐ium‐1‐yl)biphenyl], were prepared and characterized by elemental analysis, IR spectroscopy, and X‐ray diffraction. Complex 1 shows a three‐dimensional (3D) structure with threefold interpenetrating diamond topology. Complex 2 features a 3D framework with twofold interpenetrating dmc topology. Moreover, the luminescent properties of complexes 1 and 2 were also investigated.  相似文献   

3.
Four novel mixed‐ligand complexes were obtained from the reaction of maleic acid, diimine chelating ligands and Cd(OH)2 or CdO in a mixed solvent of water and methanol. The complexes were characterized by IR spectroscopy, elemental analysis, and single‐crystal X‐ray diffraction. The results show that all the four complexes are coordination polymers. [Cd(phen)(H2O)(male)]n · 2nH2O ( 1 ) and [Cd(bipy)(H2O)(male)]n · 2nH2O ( 2 ) (male = maleate; phen = 1, 10‐phenanthroline, bipy = 2, 2′‐bipyridine) are isomorphic, and the asymmetric unit is constructed by one CdII atom, a maleate group, a diimine ligand and two crystal water molecules. Each maleate group links two CdII atoms in a bis(bidentate) chelating mode, resulting in a 1D helical chain. Within [Cd(phen)(H2O)2(male)]n · 2nH2O ( 3 ), the maleate group bridges two CdII atoms in a bis(monodentate) chelating mode into a 1D helical chain along the [100] direction. The helical chain is decorated by phen groups alternatively at the two sides, and each phen plane of one chain is inserted in the void space between two adjacent phen ligands from an adjacent chain, resulting in a double zipper‐like chain. The asymmetric unit of [Cd2(phen)2(male)2]n ( 4 ) contains a CdII cation, one phen molecule, and a maleate group, and one bridging maleate group links three CdII atoms resulting in a 2D layer extending in [011] plane. The 2D networks are constructed by four kinds of rings formed by the central metal atom and maleate dianion. The thermostabilities of the four complexes were investigated.  相似文献   

4.
In the title coordination polymer, [Cd2(SO4)2(C13H8N4)(H2O)2]n, there are two crystallographically independent CdII centres with different coordination geometries. The first CdII centre is hexacoordinated by four O atoms of four sulfate ligands, one water O atom and one N atom of a 1H‐imidazo[4,5‐f][1,10]phenanthroline (IP) ligand, giving a distorted octahedral coordination environment. The second CdII centre is heptacoordinated by four O atoms of three sulfate ligands, one water O atom and two N atoms of one chelating IP ligand, resulting in a distorted monocapped anti‐trigonal prismatic geometry. The symmetry‐independent CdII ions are bridged in an alternating fashion by sulfate ligands, forming one‐dimensional ladder‐like chains which are connected through the IP ligands to form two‐dimensional layers. These two‐dimensional layers are linked by interlayer hydrogen bonds, leading to the formation of a three‐dimensional supramolecular network.  相似文献   

5.
The coordination polymers [Cd2(bbmb)2(L1)(HL1)0.5(H2O)]n ( 1 ), [Cd2(bbmb)2(L2)2(H2O) · (H2O)]n ( 2 ), and [Ni(bbmb)2(L3)]n ( 3 ), were synthesized by the hydrothermal reaction of 4,4′‐bis(benzimidazol‐1‐ylmethyl)biphenyl (bbmb) with CdII/NiII ions in the presence of three flexible aliphatic acids [tricarballylic acid (H3L1), succinate (H2L2), and adipate (H2L3)]. Complexes 1 – 3 were structurally characterized by elemental analysis, IR spectroscopy and single‐crystal and X‐ray powder diffraction analyses. Complex 1 presents a 3D 3‐nodal (3,4,4)‐connected net with 3 , 4 , 4T78 topology, 2 exhibits a 3D network with 66‐ dia topology, whereas 3 is a chain structure and further extended by hydrogen bonding interactions to form a 2D supramolecular network. Structural diversity of these complexes indicates that these frameworks could be tuned by the conformation of bbmb ligand and the different coordination modes of the aliphatic carboxylate co‐ligands. The thermal and fluorescence properties, the catalytic activities of complexes 1 – 3 in a Fenton‐like process were investigated.  相似文献   

6.
Summary New complexes of general formulae [Ni(HL)2], [ML]·H2O and [Cu(HL)X] (H2L = pyrrole-2-aldehyde Schiff bases ofS-methyl- andS-benzyldithiocarbazates; X = Cl or Br; M = NiII, CuII, ZnII or CdII) were prepared and characterized by a variety of physicochemical techniques. The Schiff bases coordinate as NS bidentate chelating agents in [Ni(HL)2] and [Cu(HL)X], and as tridentate NNS chelates in [ML] (M = NiII, CuII, ZnII or CdII). Both the [Ni(HL)2] and [NiL] complexes are diamagnetic and square-planar. Based on magnetic and spectroscopic evidence, thiolate sulphur-bridged dimeric square-planar structures are assigned to the [Cu(HL)X] and [ML] (M = NiII or CuII) complexes. The complexes ML (M = ZnII or CdII) are polymeric and octahedral.  相似文献   

7.
Three new coordination compounds, [Pb(HBDC‐I4)2(DMF)4]( 1 ) and [M(BDC‐I4)(MeOH)2(DMF)2]n (M = ZnII for 2 and MnII for ( 3 ) (H2BDC‐I4 = 2, 3, 5, 6‐tetraiodo‐1, 4‐benzenedicarboxylic acid), were synthesized and characterized by elemental analysis, IR spectroscopy, thermogravimetric (TG) analysis, and X‐ray single crystal structure analysis. Single‐crystal X‐ray diffraction reveals that 1 crystallizes in the monoclinic space group C2/c and has a discrete mononuclear structure, which is further assembled to form a two‐dimensional (2D) layer through intermolecular O–H ··· O and C–H ··· O hydrogen bonding interactions. The isostructural compounds 2 and 3 crystallize in the space group P21/c and have similar one‐dimensional (1D) chain structures that are extended into three‐dimensional (3D) supramolecular networks by interchain C–H ··· π interactions. The PbII and ZnII complexes 1 and 2 display similar emissions at 472 nm in the solid state, which essentially are intraligand transitions.  相似文献   

8.
Summary The reaction of warm alcoholic solutions of acetates of CoII, MnII, ZnII and NiII with 2, 6-diacetylpyridine andS-methylisothiosemicarbazide hydrogen iodide yielded the complexes: [Co(H2L)I2]·H2O, [Mn(H2L)(MeOH)2]I2, [Zn(H2L)(MeOH)I]I and [Ni(HL)]I, (H2L=the pentadentate pentaaza-ligand 2, 6-diacetylpyridine bis(S-methylisothiosemicarbazone)). The reaction of methanolic solutions of [Ni(HL)]I and NH4NCS or LiOAc.2H2O, give [Ni(HL)]NCS and NiL, respectively. For the complexes of CoII, MnII and ZnII, a pentagonal bipyramidal configuration is proposed, with H2L in the equatorial plane and two unidentate ligands (I and/or MeOH) in the axial positions. The complexes [Ni(HL)]X (X=I or NCS) and NiL probably have monomeric five- and dimeric six-coordinate structures, respectively, in which only the chelate ligand is involved in coordination.  相似文献   

9.
Three coordination polymers, namely {[Cu(5‐nipa)(L22)](H2O)2}n ( 1 ), [Zn(5‐nipa)(L22)(H2O)]n ( 2 ), and {[Cd2(5‐nipa)2(L22)(H2O)3](H2O)3.6}n ( 3 ), were prepared under similar synthetic method based on 1,2‐(2‐pyridyl)‐1,2,4‐triazole (L22) and ancillary ligand 5‐nitro‐isophthalic acid (5‐H2nipa) with CuII, ZnII, and CdII perchlorate, respectively. All the complexes were characterized by IR spectroscopy, elemental analysis, and powder X‐ray diffraction (PXRD) patterns. Single‐crystal X‐ray diffraction indicates that complexes 1 and 2 show similar 1D chain structures, whereas complex 3 exhibits the 2D coordination network with hcb topology. The central metal atoms show distinct coordination arrangements ranging from distorted square‐pyramid for CuII in 1 , octahedron for ZnII in 2 , to pentagonal‐bipyramid for CdII in 3 . The L22 ligand adopts the same (η32) coordination fashion in complexes 1 – 3 , while the carboxyl groups of co‐ligand 5‐nipa2– adopt monodentate fashion in 1 and 2 and bidentate chelating mode in 3 . These results indicate that the choice of metal ions exerts a significant influence on governing the target complexes. Furthermore, thermal stabilities of complexes 1 – 3 and photoluminescent properties of 2 and 3 were also studied in the solid state.  相似文献   

10.
The asymmetric unit of the title compound, [Cd(C8H4O4)(C17H8ClN5)(H2O)]n, contains one CdII atom, two half benzene‐1,4‐dicarboxylate (1,4‐bdc) anions, one 11‐chloropyrido[2′,3′:2,3]pyrimidino[5,6‐f][1,10]phenanthroline (L) ligand and one coordination water molecule. The 1,4‐bdc ligands are on inversion centers at the centroids of the arene rings. The CdII atom is six‐coordinated by two N atoms from one L ligand, three carboxylate O atoms from two different 1,4‐bdc ligands and one water O atom in a distorted octahedral coordination sphere. Each CdII center is bridged by the 1,4‐bdc dianions to give a one‐dimensional chain. π–π stacking interactions between L ligands of neighboring chains extend adjacent chains into a two‐dimensional supramolecular (6,3) network. Neighboring (6,3) networks are interpenetrated in an unusual inclined mode, resulting in a three‐dimensional framework. Additionally, the water–carboxylate O—H...O hydrogen bonds observed in the network consolidate the interpenetrating nets.  相似文献   

11.
In the title cadmium(II) coordination polymer, poly[tri‐μ4‐adipato‐bis(2‐phenyl‐1H‐1,3,7,8‐tetraazacyclopenta[l]phenanthrene‐κ2N7,N8)tricadmium(II)], [Cd3(C6H8O4)3(C19H12N4)2]n, one of the Cd atoms is in a distorted pentagonal bipyramidal coordination environment, surrounded by five O atoms from three adipate (adip) ligands and two N atoms from one 2‐phenyl‐1H‐1,3,7,8‐tetraazacyclopenta[l]phenanthrene (L) ligand. A second Cd atom occupies an inversion center and is coordinated by six O atoms from six adip ligands in a distorted octahedral geometry. The carboxylate ends of the adip ligands link CdII atoms to form unique trinuclear CdII clusters, which are further bridged by the adip linkers to produce a two‐dimensional layer structure. Topologically, each trinuclear CdII cluster is connected to four others through six adip ligands, thus resulting in a unique two‐dimensional four‐connected framework of (4,4)‐topology. This work may help the development of the coordination chemistry of 1,10‐phenanthroline derivatives.  相似文献   

12.
Two MnII coordination polymers based on the flexible bis(benzimidazole) and dicarboxylic acids, namely, [Mn(L1)(bpdc)(H2O)0.5]n ( 1 ) and [Mn(L2)(Htbi)2]n ( 2 ) [L1 = 1,4‐bis(5,6‐dimethylbenzimidazol‐1‐ylmethyl)benzene, H2bpdc = 4,4′‐biphenyldicarboxylic acid, L2 = 1,4‐bis(5,6‐dimethylbenzimidazole)butane, H2tbi = 5‐tert‐butyl isophthalic acid] were hydrothermally synthesized and characterized by elemental analysis, IR spectroscopy, as well as single‐crystal X‐ray diffraction. Both of the complexes crystallize in the triclinic P$\bar{1}$ space group and present distorted octahedral configurations. Complex 1 possesses a 2D binodal (3,5)‐connected 3,5L2 network with the point symbol of (42.67.8)(42.6), whereas 2 features a 2D uninodal 3‐connected hcb topology and the Schläfli symbol is (63). Complexes 1 and 2 ultimately are extended into 3D supramolecular framework via π–π stacking and O–H ··· O hydrogen bonding interaction, respectively. Moreover, both of the complexes manifest excellent catalytic activities for the degradation of Congo red.  相似文献   

13.
Thiosemicarbazides and their metal complexes have attracted considerable interest because of their biological activities and their flexibility, which allows the ligands to bend and rotate freely to accommodate the coordination geometries of various metal centres. Discrete copper(II) and cadmium(II) complexes have been prepared by crystallization of N‐[2‐(2‐hydroxybenzoyl)hydrazinecarbonothioyl]propanamide (H3L) with Cu(CH3COO)2 or Cd(NO3)2 in a dimethylformamide/methanol mixed‐solvent system at room temperature, affording the complexes di‐μ‐acetato‐bis{μ4‐1‐[(2‐oxidophenyl)carbonyl]‐2‐(propanamidomethanethioyl)hydrazine‐1,2‐diido}tetracopper(II) dimethylformamide disolvate, [Cu4(C11H10N3O3S)2(C2H3O2)2]·2C3H7NO, (I), and bis{μ2‐[(2‐hydroxyphenyl)formamido](propanamidomethanethioyl)azanido}bis[(4,4′‐bipyridine)nitratocadmium(II)] dihydrate, [Cd2(C11H12N3O3S)2(NO3)2(C10H8N2)2]·2H2O, (II). Complex (I) consists of four CuII cations, two μ4‐bridging trianionic ligands and two μ2‐bridging acetate ligands, while complex (II) is composed of two CdII cations, two μ2‐bridging monoanionic ligands, two nitrate ligands and two 4,4′‐bipyridine ligands. These discrete complexes are connected by hydrogen bonds and van der Waals interactions to form a three‐dimensional supramolecular architecture. Compared with (I), the phenolic hydroxy group and hydrazide N atom of the thiosemicarbazide ligand of (II) are not involved in coordination and lead to a binuclear CdII complex. This different coordination mode may be attributed to the larger ionic radius of the CdII ion compared with the CuII ion.  相似文献   

14.
A new cadmium coordination polymer, [Cd(C5H2N2O4)(H2O)2]n, possesses a one‐dimensional zigzag chain structure built from CdII centers bridged sequentially by pairs of O and N atoms of the 5‐carboxyimidazole‐4‐carboxylate ligand. The CdII center is in a distorted octahedral geometry, being coordinated by two O atoms from two coordinated water mol­ecules [Cd—O = 2.322 (7) and 2.364 (7) Å], and by two N atoms [Cd—N = 2.222 (6) and 2.232 (6) Å] and two carboxyl O atoms [Cd—O = 2.383 (6) and 2.414 (6) Å] from two 5‐carboxyimidazole‐4‐carboxylate ligands.  相似文献   

15.
The hydrothermal reaction of 2‐(quinolin‐8‐yloxy)acetonitrile and Cd(ClO4)2 yielded the noncentrosymmetric coordination complex tetrakis[μ‐2‐(quinolin‐8‐yloxy)acetato]tetrakis[μ‐2‐(quinolin‐8‐yloxy)acetonitrile]tetracadmium tetrakis(perchlorate) dihydrate, [Cd4(C11H8NO3)4(C11H8N2O)4](ClO4)4·2H2O. The local coordination environment around the CdII cation can be best described as a capped octahedron defined by two N atoms and five O atoms from three ligands. The CdII cations are linked by the ligands with Cd—O—Cd and Cd—O—C—C—O—Cd bridges, forming tetranuclear units, there being two independent tertranuclear units in the structure. The fourfold rotoinversion centre sits at the centre of each Cd4 core. The two perchlorate anions in the asymmetric unit are linked by the water molecule through O—H...O hydrogen bonds.  相似文献   

16.
Two three‐dimensional (3D) CdII coordination polymers, namely poly[[di‐μ‐aqua‐diaquabis{μ5‐4,4′,4′′‐[benzene‐1,3,5‐triyltris(oxy)]tribenzoato}tricadmium(II)] dihydrate], {[Cd3(C27H15O9)2(H2O)4]·2H2O}n, (I), and poly[[aqua{μ6‐4,4′,4′′‐[benzene‐1,3,5‐triyltris(oxy)]tribenzoato}(μ‐formato)[μ‐1,1′‐(1,4‐phenylene)bis(1H‐imidazole)]dicadmium(II)] dihydrate], {[Cd2(C27H15O9)(C12H10N4)(HCOO)(H2O)]·2H2O}n, (II), have been hydrothermally synthesized from the reaction system containing Cd(NO3)2·4H2O and the flexible tripodal ligand 1,3,5‐tris(4‐carboxyphenoxy)benzene (H3tcpb) via tuning of the auxiliary ligand. Both complexes have been characterized by single‐crystal X‐ray diffraction analysis, elemental analysis, IR spectra, powder X‐ray diffraction and thermogravimetric analysis. Complex (I) is a 3D framework constructed from trinuclear structural units and tcpb3? ligands in a μ5‐coordination mode. The central CdII atom of the trinuclear unit is located on a crystallographic inversion centre and adopts an octahedral geometry. The metal atoms are bridged by four synsyn carboxylate groups and two μ2‐water molecules to form trinuclear [Cd3(COO)42‐H2O)2] secondary building units (SBUs). These SBUs are incorporated into clusters by bridging carboxylate groups to produce pillars along the c axis. The one‐dimensional inorganic pillars are connected by tcpb3? linkers in a μ5‐coordination mode, thus forming a 3D network; its topology corresponds to the point symbol (42.62.82)(44.62)2(45.66.84)2. In contrast to (I), complex (II) is characterized by a 3D framework based on dinuclear cadmium SBUs, i.e. [Cd2(COO)3]. The two symmetry‐independent CdII ions display different coordinated geometries, namely octahedral [CdN2O4] and monocapped octahedral [CdO7]. The dinuclear SBUs are incorporated into clusters by bridging formate groups to produce pillars along the c axis. These pillars are further bridged either by tcpb3? ligands into sheets or by 1,4‐bis(imidazol‐1‐yl)benzene ligands into undulating layers, and finally these two‐dimensional surfaces interweave, forming a 3D structure with the point symbol (4.62)(47.614). Compound (II) exhibits reversible I2 uptake of 56.8 mg g?1 with apparent changes in the visible colour and the UV–Vis and fluorescence spectra, and therefore may be regarded as a potential reagent for the capture and release of I2.  相似文献   

17.
Summary Vanillin thiosemicarbazone (VTSC) has been used to isolate the complexes of the types [M(VTSC)2(H2O)2]X2 (M=MnII, FeII, CoII, or NiII and X=Cl) and [M(VTSC)X2]H2O (M=CuII, ZnII, CdII or HgII and X=Cl). Probable structures of these complexes are suggested on the basis of elemental analysis, molar conductance, magnetic moment and electronic and i.r. spectral data. The fungicidal activity of VTSC and the isolated complexes has been evaluated on pathogenic fungi,Alternaria (Sp.),Paecilomyces (Sp.) andPestalotia (Sp.).On leave from the University of Myosore.  相似文献   

18.
Poly[(μ4‐pyrazine‐2,5‐dicarboxylato)cadmium(II)], [Cd(C6H2N2O4)]n or [Cd(pzdc)]n (pzdc is the pyrazine‐2,5‐dicarboxylate dianion), has been synthesized hydrothermally. The asymmetric unit consists of a CdII atom and two independent halves of pzdc ligands that can be expanded via inversion through the centres of the ligands so that each ligand binds to four CdII atoms with the same binding mode using six donor atoms. The CdII centre is in a distorted octahedral coordination geometry with four O‐ and two N‐atom donors from four pzdc ligands. The infinite linkage of the metal atoms and ligands forms a three‐dimensional framework with a rectangular channel which is so narrow that there is no measurable void space in the overall structure. This coordination polymer represents the first example of (4,4,4)‐connected three‐nodal framework.  相似文献   

19.
The title complex, [CdCl(NCS)(C10H8N2)]n, represents an unusual CdII coordination polymer constructed by two types of anionic bridges and 2,2′‐bipyridyl (bipy) terminal ligands. These two types of bridges are arranged around inversion centers. The distorted octahedral coordination of the CdII center is provided by two chloride ions, one N‐ and one S‐donor atom from two thiocyanate ions, and a pair of N atoms from the chelating bipy ligand. Interestingly, adjacent CdII ions are interconnected alternately by paired chloride [Cd...Cd = 3.916 (1) Å] and thiocyanate bridges [Cd...Cd = 5.936 (1) Å] to generate an infinite one‐dimensional coordination chain. Furthermore, weak interchain C—H...S interactions between the bipy components and thiocyanate ions lead to the formation of a layered supramolecular structure.  相似文献   

20.
Complexes of N-phthaloylglycinate (N-phthgly) and CoII, NiII, CuII, ZnII and CdII containing imidazole (imi), N-methylimidazole (mimi), 2,2-bipyridyl (bipy) and 1,10-phenanthroline (phen), and tridentate amines such as 2,2,2-terpyridine (terpy) and 2,4,6-(2-pyridyl)s-triazine (tptz), were prepared and characterized by conventional methods, i.r. spectra and by thermogravimetric analysis. For imi and mimi ternary complexes, the general formula [M(imi/mimi)2(N-phthgly)2nH2O, where M = CoII, NiII, CuII and ZnII applies. For CdII ternary complexes with imi, [Cd(imi)3(N-phthgly)2]·2H2O applies. For the bi and tridentate ligands, ternary complexes of the formula [M(L)(N-phthgly)2nH2O were obtained, where M = CoII, NiII, CuII and ZnII; L = bipy, phen, tptz and terpy. In all complexes, N-phthgly acts as a monodentate ligand, coordinating metal ions through the carboxylate oxygen, except for the ternary complexes of CoII, NiII and CuII with mimi and CuII and ZnII with imi, where the N-phthgly acts as a bidentate ligand, coordinating the metal ions through both carboxylate oxygen atoms.  相似文献   

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