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1.
The title hydrated ionic complex, [Ni(CH3COO)(C12H12N2)2]ClO4·H2O or [Ni(ac)(5,5′‐dmbpy)2]ClO4·H2O (where 5,5′‐dmbpy is 5,5′‐dimethyl‐2,2′‐bipyridine and ac is acetate), (1), was isolated as violet crystals from the aqueous ethanolic nickel acetate–5,5′‐dmbpy–KClO4 system. Within the complex cation, the NiII atom is hexacoordinated by two chelating 5,5′‐dmbpy ligands and one chelating ac ligand. The mean Ni—N and Ni—O bond lengths are 2.0628 (17) and 2.1341 (15) Å, respectively. The water solvent molecule is disordered over two partially occupied positions and links two complex cations and two perchlorate anions into hydrogen‐bonded centrosymmetric dimers, which are further connected by π–π interactions. The magnetic properties of (1) at low temperatures are governed by the action of single‐ion anisotropy, D, which arises from the reduced local symmetry of the cis‐NiO2N4 chromophore. The fitting of the variable‐temperature magnetic data (2–300 K) gives giso = 2.134 and D/hc = 3.13 cm−1.  相似文献   

2.
In the dinuclear molecule of [(C5H4N)3N]2CdCl2CdCl2, one cadmium is octahedrally coordinated by a Cl2N4 donor set and the other cadmium is tetrahedrally coordinated by four chlorine atoms. The dinuclear units are connected by π–π interactions to give a two‐dimensional network. Copyright © 2003 John Wiley & Sons, Ltd.  相似文献   

3.
Three photoluminescent complexes containing either ZnII or CdII have been synthesized and their structures determined. Bis[4‐amino‐3,5‐bis(pyridin‐2‐yl)‐1,2,4‐triazole‐κ2N 1,N 5]bis(dicyanamido‐κN 1)zinc(II), [Zn(C12H10N6)2(C2N3)2], (I), bis[4‐amino‐3,5‐bis(pyridin‐2‐yl)‐1,2,4‐triazole‐κ2N 1,N 5]bis(dicyanamido‐κN 1)cadmium(II), [Cd(C12H10N6)2(C2N3)2], (II), and bis[4‐amino‐3,5‐bis(pyridin‐2‐yl)‐1,2,4‐triazole‐κ2N 1,N 5]bis(tricyanomethanido‐κN 1)cadmium(II), [Cd(C12H10N6)2(C4N3)2], (III), all crystallize in the space group P , with the metal centres lying on centres of inversion, but neither analogues (I) and (II) nor CdII complexes (II) and (III) are isomorphous. A combination of N—H…N and C—H…N hydrogen bonds and π–π stacking interactions generates three‐dimensional framework structures in (I) and (II), and a sheet structure in (III). The photoluminescence spectra of (I)–(III) indicate that the energies of the π–π* transitions in the coordinated triazole ligand are modified by minor changes of the ligand geometry associated with coordination to the metal centres.  相似文献   

4.
A series of neutral complexes, namely, [N‐(2‐hydroxy‐4‐nitrophenyl)‐3‐hydroxysalicylideneiminato]‐ diphenyltin(IV) ( Ia ), [N‐(2‐hydroxy‐4‐nitrophenyl)‐3‐methoxysalicylideneiminato]diphenyltin(IV) ( IIa ) and [N‐(2‐hydroxy‐4‐nitrophenyl)‐3‐ethoxysalicylideneiminato]diphenyltin(IV) ( IIIa ) were prepared by the reaction of diphenyltin dichloride on the corresponding Schiff bases. The Schiff bases were the reaction products of 2‐hydroxy‐4‐nitroaniline and appropriate salicylaldehydes. All the compounds were characterized by elemental analysis, 1H‐NMR, 13C‐NMR, IR and mass spectroscopy. Compound IIIa was also characterized by single crystal X‐ray diffraction and shows a C2NO2 coordination geometry nearly half‐way between a trigonal bipyramidal and square pyramidal arrangement. In the solid state, π? π interactions exist between the aniline fragments of neighbouring molecules. Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   

5.
Due to their versatile coordination modes and metal‐binding conformations, triazolyl ligands can provide a wide range of possibilities for the construction of supramolecular structures. Seven mononuclear transition metal complexes with different structural forms, namely aquabis[3‐(4‐methylphenyl)‐5‐(pyridin‐2‐yl)‐1H‐1,2,4‐triazolato‐κ2N 1,N 5]zinc(II), [Zn(C14H11N4)2(H2O)], (I), bis[5‐(4‐methylphenyl)‐3‐(pyridin‐2‐yl)‐1H‐1,2,4‐triazole‐κ2N 3,N 4]bis(nitrato‐κO )zinc(II), [Zn(NO3)2(C14H12N4)2], (II), bis(methanol‐κO )bis[3‐(4‐methylphenyl)‐5‐(pyridin‐2‐yl)‐1H‐1,2,4‐triazolato‐κ2N 1,N 5]zinc(II), [Zn(C14H11N4)2(CH4O)2], (III), diiodidobis[5‐(4‐methylphenyl)‐3‐(pyridin‐2‐yl)‐1H‐1,2,4‐triazole‐κ2N 3,N 4]cadmium(II), [CdI2(C14H12N4)2], (IV), bis[5‐(4‐methylphenyl)‐3‐(pyridin‐2‐yl)‐1H‐1,2,4‐triazole‐κ2N 3,N 4]bis(nitrato‐κO )cadmium(II), [Cd(NO3)2(C14H12N4)2], (V), aquabis[3‐(4‐methylphenyl)‐5‐(pyridin‐2‐yl)‐1H‐1,2,4‐triazolato‐κ2N 1,N 5]cobalt(II), [Co(C14H11N4)2(H2O)], (VI), and diaquabis[3‐(4‐methylphenyl)‐5‐(pyridin‐2‐yl)‐1H‐1,2,4‐triazolato‐κ2N 1,N 5]nickel(II), [Ni(C14H11N4)2(H2O)2], (VII), have been prepared by the reaction of transition metal salts (ZnII, CdII, CoII and NiII) with 3‐(4‐methylphenyl)‐5‐(pyridin‐2‐yl)‐1H‐1,2,4‐triazole (pymphtzH) under either ambient or hydrothermal conditions. These compounds have been characterized by elemental analysis, IR spectroscopy and single‐crystal X‐ray diffraction. All the complexes form three‐dimensional supramolecular structures through hydrogen bonds or through π–π stacking interactions between the centroids of the pyridyl or arene rings. The pymphtzH and pymphtz entities act as bidentate coordinating ligands in each structure. Moreover, all the pyridyl N atoms are coordinated to metal atoms (Zn, Cd, Co or Ni). The N atom in the 4‐position of the triazole group is coordinated to the Zn and Cd atoms in the crystal structures of (II), (IV) and (V), while the N atom in the 1‐position of the triazolate group is coordinated to the Zn, Co and Ni atoms in (I), (III), (VI) and (VII).  相似文献   

6.
Despite the large number of reported crystalline structures of coordination complexes bearing pyridines as ligands, the relevance of π–π interactions among these hereroaromatic systems in the stabilization of their supramolecular structures and properties is not very well documented in the recent literature. The title compound, [CoCl2(C5H6N2)2], was obtained as bright‐blue crystals suitable for single‐crystal X‐ray diffraction analysis from the reaction of 4‐aminopyridine with cobalt(II) chloride in ethanol. The new complex was fully characterized by a variety of spectroscopic techniques and single‐crystal X‐ray diffraction. The crystal structure showed a tetrahedral complex stabilized mainly by bidimensional motifs constructed by π–π interactions with large horizontal displacements between the 4‐aminopyridine units, and N—H…Cl hydrogen bonds. Other short contacts, such as C—H…Cl interactions, complete the three‐dimensional arrangement. The supramolecular investigation was extended by statistical studies using the Cambridge Structural Database and a Hirshfeld surface analysis.  相似文献   

7.
Zinc thiocyanate complexes have been found to be biologically active compounds. Zinc is also an essential element for the normal function of most organisms and is the main constituent in a number of metalloenzyme proteins. Pyrimidine and aminopyrimidine derivatives are biologically very important as they are components of nucleic acids. Thiocyanate ions can bridge metal ions by employing both their N and S atoms for coordination. They can play an important role in assembling different coordination structures and yield an interesting variety of one‐, two‐ and three‐dimensional polymeric metal–thiocyanate supramolecular frameworks. The structure of a new zinc thiocyanate–aminopyrimidine organic–inorganic compound, (C6H9ClN3)2[Zn(NCS)4]·2C6H8ClN3·2H2O, is reported. The asymmetric unit consist of half a tetrathiocyanatozinc(II) dianion, an uncoordinated 4‐amino‐5‐chloro‐2,6‐dimethylpyrimidinium cation, a 4‐amino‐5‐chloro‐2,6‐dimethylpyrimidine molecule and a water molecule. The ZnII atom adopts a distorted tetrahedral coordination geometry and is coordinated by four N atoms from the thiocyanate anions. The ZnII atom is located on a special position (twofold axis of symmetry). The pyrimidinium cation and the pyrimidine molecule are not coordinated to the ZnII atom, but are hydrogen bonded to the uncoordinated water molecules and the metal‐coordinated thiocyanate ligands. The pyrimidine molecules and pyrimidinium cations also form base‐pair‐like structures with an R22(8) ring motif via N—H…N hydrogen bonds. The crystal structure is further stabilized by intermolecular N—H…O, O—H…S, N—H…S and O—H…N hydrogen bonds, by intramolecular N—H…Cl and C—H…Cl hydrogen bonds, and also by π–π stacking interactions.  相似文献   

8.
2‐{1‐[(Pyrazin‐2‐ylformamido)methyl]cyclohexyl}acetic acid (Pyr‐Gpn‐OH), C14H19N3O3, is an N‐protected derivative of gabapentin (Gpn). The compound crystallizes in the triclinic space group P and the molecular conformation is stabilized by intramolecular five‐ (C5) and seven‐membered (C7) hydrogen‐bonded rings. The packing of the molecules reveals intermolecular O—H...O and C—H...N hydrogen bonds, together with π–π interactions.  相似文献   

9.
The zinc(II) atom in the molecule of [(C5H4N)3N]ZnI2 is tetrahedrally coordinated to two nitrogen atoms of the tris(2‐pyridyl)amine ligand and two iodides. The coordination moieties are connected to give a linear structure by intermolecular π–π interactions between the pyridyl rings. Copyright © 2003 John Wiley & Sons, Ltd.  相似文献   

10.
4,4′‐Bipyridine‐1,1′‐diium (H2bipy) acetylenedicarboxylate, C10H12N22+·C4O42−, (1), is a new member of a family of related structures with similar unit‐cell parameters. The structures in this family reported previously [Chen et al. (2012). CrystEngComm, 14 , 6400–6403] are (H2bipy)[Cu(ox)2] (ox is oxalate), (2), (H2bipy)[NaH(ox)2], (3), and (H2bipy)[H2(ox)2], (4). Compound (1) has a one‐dimensional structure, in which H2bipy2+ cations and acetylenedicarboxylate (ADC2−) anions are linked through a typical supramolecular synthon, i.e.R22(7), and form linear `–cation–anion–' ribbons. Through an array of nonclassical C—H...O hydrogen bonds, adjacent ribbons interact to give two‐dimensional sheets. These sheets stack to form a layered structure viaπ–π interactions between the H2bipy2+ cations of neighbouring layers. The supramolecular isostructurality of compounds (1)–(4) is ascribed to the synergistic effect of multiple interactions in these structures. The balanced strong and weak intermolecular interactions stabilizing this structure type include strong charge‐assisted N—H...O hydrogen bonds, C—H...O contacts and π–π interactions.  相似文献   

11.
The reaction of NiCl2, K2C2O4·H2O and 2,2′‐bipyridine (bpy) in water–ethanol solution at 281 K yields light‐purple needles of the new pentahydrate of bis(2,2′‐bipyridine)oxalatonickel(II), [Ni(C2O4)(C10H8N2)2]·5H2O or [Ni(ox)(bpy)2]·5H2O, while at room temperature, deep‐pink prisms of the previously reported tetrahydrate [Ni(ox)(bpy)2]·4H2O [Román, Luque, Guzmán‐Miralles & Beitia (1995), Polyhedron, 14 , 2863–2869] were gathered. The asymmetric unit in the crystal structure of the new pentahydrate incorporates the discrete molecular complex [Ni(ox)(bpy)2] and five solvent water molecules. Within the complex molecule, all three ligands are bonded as chelates. The complex molecules are involved in an extended system of hydrogen bonds with the solvent water molecules. Additionally, π–π interactions also contribute to the stabilization of the extended structure. The dehydration of the pentahydrate starts at 323 K and proceeds in at least two steps as determined by thermal analysis.  相似文献   

12.
The new asymmetrical organic ligand 2‐{4‐[(1H‐imidazol‐1‐yl)methyl]phenyl}‐5‐(pyridin‐4‐yl)‐1,3,4‐oxadiazole ( L , C17H13N5O), containing pyridine and imidazole terminal groups, as well as potential oxdiazole coordination sites, was designed and synthesized. The coordination chemistry of L with soft AgI, CuI and CdII metal ions was investigated and three new coordination polymers (CPs), namely, catena‐poly[[silver(I)‐μ‐2‐{4‐[(1H‐imidazol‐1‐yl)methyl]phenyl}‐5‐(pyridin‐4‐yl)‐1,3,4‐oxadiazole] hexafluoridophosphate], {[Ag( L )]PF6}n, catena‐poly[[copper(I)‐di‐μ‐iodido‐copper(I)‐bis(μ‐2‐{4‐[(1H‐imidazol‐1‐yl)methyl]phenyl}‐5‐(pyridin‐4‐yl)‐1,3,4‐oxadiazole)] 1,4‐dioxane monosolvate], {[Cu2I2( L )2]·C4H8O2}n, and catena‐poly[[[dinitratocopper(II)]‐bis(μ‐2‐{4‐[(1H‐imidazol‐1‐yl)methyl]phenyl}‐5‐(pyridin‐4‐yl)‐1,3,4‐oxadiazole)]–methanol–water (1/1/0.65)], {[Cd( L )2(NO3)2]·2CH4O·0.65H2O}n, were obtained. The experimental results show that ligand L coordinates easily with linear AgI, tetrahedral CuI and octahedral CdII metal atoms to form one‐dimensional polymeric structures. The intermediate oxadiazole ring does not participate in the coordination interactions with the metal ions. In all three CPs, weak π–π interactions between the nearly coplanar pyridine, oxadiazole and benzene rings play an important role in the packing of the polymeric chains.  相似文献   

13.
Carbon monoxide (CO) has recently been identified as a gaseous signaling molecule that exerts various salutary effects in mammalian pathophysiology. Photoactive metal carbonyl complexes (photoCORMs) are ideal exogenous candidates for more controllable and site‐specific CO delivery compared to gaseous CO. Along this line, our group has been engaged for the past few years in developing group‐7‐based photoCORMs towards the efficient eradication of various malignant cells. Moreover, several such complexes can be tracked within cancerous cells by virtue of their luminescence. The inherent luminecscent nature of some photoCORMs and the change in emission wavelength upon CO release also provide a covenient means to track the entry of the prodrug and, in some cases, both the entry and CO release from the prodrug. In continuation of the research circumscribing the development of trackable photoCORMs and also to graft such molecules covalently to conventional delivery vehicles, we report herein the synthesis and structures of three rhenium carbonyl complexes, namely, fac‐tricarbonyl[2‐(pyridin‐2‐yl)‐1,3‐benzothiazole‐κ2N ,N ′](4‐vinylpyridine‐κN )rhenium(I) trifluoromethanesulfonate, [Re(C7H7N)(C12H8N2S)(CO)3](CF3SO3), ( 1 ), fac‐tricarbonyl[2‐(quinolin‐2‐yl)‐1,3‐benzothiazole‐κ2N ,N ′](4‐vinylpyridine‐κN )rhenium(I) trifluoromethanesulfonate, [Re(C7H7N)(C16H10N2S)(CO)3](CF3SO3), ( 2 ), and fac‐tricarbonyl[1,10‐phenanthroline‐κ2N ,N ′](4‐vinylpyridine‐κN )rhenium(I) trifluoromethanesulfonate, [Re(C7H7N)(C12H8N2)(CO)3](CF3SO3), ( 3 ). In all three complexes, the ReI center resides in a distorted octahedral coordination environment. These complexes exhibit CO release upon exposure to low‐power UV light. The apparent CO release rates of the complexes have been measured to assess their comparative CO‐donating capacity. The three complexes are highly luminescent and this in turn provides a convenient way to track the entry of the prodrug molecules within biological targets.  相似文献   

14.
Two copper(I)‐based frameworks of complexes {[Cu(L)2(ClO4)]?CH3CN}( 2 ) and {[Cu(L)(ClO4)]? 2CH3CN} ( 3 ) (L = 1,3,5‐tris(4‐pyridylethynyl) benzene) were produced by reacting [Cu(MeCN)4(ClO4)] with different amounts of a ligand (L) using a hydrothermal method at temperatures of up to 130°C. The nitrogen atoms in the pyridine moieties of the ligand coordinate to the Cu(I) ion. The charge on the Cu(I) ion can be stabilized by extending the degree of conjugation in the system and by taking advantage of its highly symmetrical structure. The large degree of conjugation also supports numerous π–π interactions in the framework.  相似文献   

15.
A novel dinuclear bismuth(III) coordination compound, [Bi2(C7H3NO4)2(N3)2(C12H8N2)2]·4H2O, has been synthesized by an ionothermal method and characterized by elemental analysis, energy‐dispersive X‐ray spectroscopy, IR, X‐ray photoelectron spectroscopy and single‐crystal X‐ray diffraction. The molecular structure consists of one centrosymmetric dinuclear neutral fragment and four water molecules. Within the dinuclear fragment, each BiIII centre is seven‐coordinated by three O atoms and four N atoms. The coordination geometry of each BiIII atom is distorted pentagonal–bipyramidal (BiO3N4), with one azide N atom and one bridging carboxylate O atom located in axial positions. The carboxylate O atoms and water molecules are assembled via O—H...O hydrogen bonds, resulting in the formation of a three‐dimensional supramolecular structure. Two types of π–π stacking interactions are found, with centroid‐to‐centroid distances of 3.461 (4) and 3.641 (4) Å.  相似文献   

16.
Molecular recognition continues to be an area of keen interest for supramolecular chemists. The investigated [M( L )2]2+ metallo‐ligands (M=PdII, PtII, L =2‐(1‐(pyridine‐4‐methyl)‐1 H‐1,2,3‐triazol‐4‐yl)pyridine) form a planar cationic panel with vacant pyridyl binding sites. They interact with planar neutral aromatic guests through π–π and/or metallophilic interactions. In some cases, the metallo‐ligands also interacted in the solid state with AgI either through coordination to the pendant pyridyl arms, or through metal–metal interactions, forming coordination polymers. We have therefore developed a system that reliably recognises a planar electron‐rich guest in solution and in the solid state, and shows the potential to link the resultant host–guest adducts into extended solid‐state structures. The facile synthesis and ready functionalisation of 2‐pyridyl‐1,2,3‐triazole ligands through copper(I)‐catalyzed azide–alkyne cycloaddition (CuAAC) “click” chemistry should allow for ready tuning of the electronic properties of adducts formed from these systems.  相似文献   

17.
The enhancement of the binding between halide anions and a Lewis acidic uranyl–salophen receptor has been achieved by the introduction of pendant electron‐deficient arene units into the receptor skeleton. The association and the occurrence of the elusive anion–π interaction with halide anions (as tetrabutylammonium salts) have been demonstrated in solution and in the solid state, providing unambiguous evidence on the interplay of the concerted interactions responsible for the anion binding.  相似文献   

18.
The blue copper complex [Cu2(H2O)2(phen)2(OH)2][Cu2(phen)2(OH)2(CO3)2] · 10 H2O, which was prepared by reaction of 1,10‐phenanthroline monohydrate, CuCl2 · 2 H2O and Na2CO3 in the presence of succinic acid in CH3OH/H2O at pH = 13.0, crystallized in the triclinic space group P1 (no. 2) with cell dimensions: a = 9.515(1) Å, b = 12.039(1) Å, c = 12.412(2) Å, α = 70.16(1)°, β = 85.45(1)°, γ = 81.85(1)°, V = 1323.2(2) Å3, Z = 1. The crystal structure consists of dinuclear [Cu2(H2O)2(phen)2(OH)2]2+ complex cations, dinuclear [Cu2(phen)2(OH)2(CO3)2]2– complex anions and hydrogen bonded H2O molecules. In both the centrosymmetric dinuclear cation and anion, the Cu atoms are coordinated by two N atoms of one phen ligand, three O atoms of two μ‐OH groups and respectively one H2O molecule or one CO32– anion to complete distorted [CuN2O3] square‐pyramids with the H2O molecule or the CO32– anion at the apical position (equatorial d(Cu–O) = 1.939–1.961 Å, d(Cu–N) = 2.026–2.051 Å and axial d(Cu–O) = 2.194, 2.252 Å). Two adjacent [CuN2O3] square pyramids are condensed via two μ‐OH groups. Through the interionic hydrogen bonds, the dinuclear cations and anions are linked into 1D chains with parallel phen ligands on both sides. Interdigitation of phen ligands of neighboring 1D chains generated 2D layers, between which the hydrogen bonded water molecules are sandwiched.  相似文献   

19.
To explore the operational role of noncovalent interactions in supramolecular architectures with designed topologies, a series of solid‐state structures of 2‐ and 4‐formylphenyl 4‐substituted benzenesulfonates was investigated. The compounds are 2‐formylphenyl 4‐methylbenzenesulfonate, C14H12O4S, 3a , 2‐formylphenyl 4‐chlorobenzenesulfonate, C13H9ClO4S, 3b , 2‐formylphenyl 4‐bromobenzenesulfonate, C13H9BrO4S, 3c , 4‐formylphenyl 4‐methylbenzenesulfonate, C14H12O4S, 4a , 4‐formylphenyl 4‐chlorobenzenesulfonate, 4b , C13H9ClO4S, and 4‐formylphenyl 4‐bromobenzenesulfonate, C13H9BrO4S, 4c . The title compounds were synthesized under basic conditions from salicylaldehyde/4‐hydroxybenzaldehydes and various aryl sulfonyl chlorides. Remarkably, halogen‐bonding interactions are found to be important to rationalize the solid‐state crystal structures. In particular, the formation of O…X (X = Cl and Br) and type I XX halogen‐bonding interactions have been analyzed by means of density functional theory (DFT) calculations and characterized using Bader's theory of `atoms in molecules' and molecular electrostatic potential (MEP) surfaces, confirming the relevance and stabilizing nature of these interactions. They have been compared to antiparallel π‐stacking interactions that are formed between the arylsulfonates.  相似文献   

20.
(E)-[(2-Cyclohexenyl)vinyl]triaryitin (aryl=phenyl, p-tolyl) were synthesized and characterized by elemental analysis, IR, 1H NMR spectroscopy. The crystal structure of (E-)[(2 cyclohexenyl)vinyl]triphenyltin was also determined by the X-ray diffraction. Experiments show that this compound has the conjugated system, which makes it have possible bioactivity and antitumor activity.  相似文献   

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