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1.
The supramolecular silver(I)‐thiolate complex [Ag(μ2‐SC4N2H4)2(SCN)]n has been prepared from the reaction of AgSCN and pyrimidine‐2‐thiol in DMF. X‐ray diffraction analysis shows that the supramolecular structure exhibits one‐dimensional chain through the secondary Ag‐S interactions and the chains are further linked by strong hydrogen bonds to form a three dimensional network. The luminescence effect from the silver‐centered state of S→Ag LMCT in solid state is different from that in solution due to the secondary Ag‐S interactions.  相似文献   

2.
Five mono‐nuclear silver(I) complexes with the ligand 2,9‐dimethyl‐1,10‐phenanthroline, namely [Ag(DPEphos)(dmp)]BF4 ( 1 ), [Ag(DPEphos)(dmp)]CF3SO3 ( 2 ), [Ag(DPEphos)(dmp)]ClO4 ( 3 ), [Ag(DPEphos)(dmp)]NO3 ( 4 ), and [Ag(dppb)(dmp)]NO3 · CH3OH ( 5 ) {DPEphos = bis[2‐(diphenylphosphanyl)phenyl]ether, dppb = 1,2‐bis(diphenylphosphanyl)benzene, dmp = 2,9‐dimethyl‐1,10‐phenanthroline} were characterized by X‐ray diffraction, IR, 1H NMR, 31P NMR and fluorescence spectroscopy. Their terahertz (THz) time‐domain spectra were also studied. In these complexes the silver(I), which is coordinated by two kinds of chelating ligands, adopts four‐coordinate modes to generate mono‐nuclear structures. In complexes 1 , 3 – 5 , offset π ··· π weak interactions exist between the neighboring benzene rings. In the 31P NMR spectra, there exist splitting signals (dd), which can be attributed to the coupling of the 107,109Ag–31P. All the emission peaks of these complexes are attributed to ligand‐centered excited states.  相似文献   

3.
Two new silver(I) trans‐cinnamates, namely [Ag(2‐cca)(H2O)]2 ( 1 ) and [Ag(4‐cca)]n ( 2 ) (2‐ccaH = 2‐chlorocinnamic acid and 4‐ccaH = 4‐chlorocinnamic acid), were synthesized and structurally characterized. Single crystal X‐ray studies reveal that each silver(I) atom in 1 is two‐coordinate by a 2‐chlorocinnamate ligand and one water molecule to afford a discrete centrosymmetric dimer with the ligand‐unsupported Ag···Ag interactions (3.218(4) Å), while a pair of symmetry‐related silver(I) atoms in 2 are clamped by two μ2‐η11 4‐chlorocinnamate ligands to yield a binuclear silver(I) moiety incorporating a ligand‐supported Ag···Ag interaction (2.819(5) Å). Both complexes 1 and 2 show potent urease inhibitory activities with the respective IC50 values of 0.66 and 1.10 μM.  相似文献   

4.
Five mono‐nuclear silver (I) complexes with 6,7‐dicyanodipyridoquinoxaline ligand, namely {[Ag(DPEphos)(dicnq)]NO3}2 · CH3OH ( 1 ), [Ag(DPEphos)(dicnq)]BF4 · CH3OH ( 2 ), [Ag(XANTphos)(dicnq)]CF3SO3 ( 3 ), {[Ag(XANTphos)(dicnq)]NO3}2 ( 4 ), and [Ag(XANTphos)(dicnq)]ClO4 · CH2Cl2 ( 5 ) {DPEphos = bis[2‐(diphenylphosphanyl)phenyl]ether, dicnq = 6,7‐dicyanodipyridoquinoxaline, XANTphos = 9,9‐dimethyl‐4,5‐bis(diphenylphosphanyl)xanthene} were characterized by X‐ray diffraction, IR, 1H NMR, 31P NMR, fluorescence spectra, and terahertz time‐domain spectra (THz‐TDS). In the five complexes the AgI, which is coordinated by two kinds of chelating ligands, adopts four‐coordinate modes to generate mono‐nuclear structures. The C–H ··· π interactions lead to formation of a 1D infinite chain for complexes 2 and 3 . The crystal packing of complexes 1 and 5 reveal that they form 3D supermolecular network by several pairs of C–H ··· π interactions. The emissions of these complexes are attributed to ligands‐centered [π–π*] transition based on both of the P‐donor and N‐donor ligands.  相似文献   

5.
The three‐dimensional coordination polymer poly[[bis(μ3‐2‐aminoacetato)di‐μ‐aqua‐μ3‐(naphthalene‐1,5‐disulfonato)‐hexasilver(I)] dihydrate], {[Ag6(C10H6O6S2)(C2H4NO2)4(H2O)2]·2H2O}n, based on mixed naphthalene‐1,5‐disulfonate (L1) and 2‐aminoacetate (L2) ligands, contains two AgI centres (Ag1 and Ag4) in general positions, and another two (Ag2 and Ag3) on inversion centres. Ag1 is five‐coordinated by three O atoms from one L1 anion, one L2 anion and one water molecule, one N atom from one L2 anion and one AgI cation in a distorted trigonal–bipyramidal coordination geometry. Ag2 is surrounded by four O atoms from two L2 anions and two water molecules, and two AgI cations in a slightly octahedral coordination geometry. Ag3 is four‐coordinated by two O atoms from two L2 anions and two AgI cations in a slightly distorted square geometry, while Ag4 is also four‐coordinated by two O atoms from one L1 and one L2 ligand, one N atom from another L2 anion, and one AgI cation, exhibiting a distorted tetrahedral coordination geometry. In the crystal structure, there are two one‐dimensional chains nearly perpendicular to one another (interchain angle = 87.0°). The chains are connected by water molecules to give a two‐dimensional layer, and the layers are further bridged by L1 anions to generate a novel three‐dimensional framework. Moreover, hydrogen‐bonding interactions consolidate the network.  相似文献   

6.
The reaction of Ag2SO4 and bpp (bpp = 1,3‐bis(4‐pyridyl)propane) in H2O afforded the complex [Ag2(bpp)2(SO4) · 6.5H2O·CH3OH]n, 1. The IR and TGA have been recorded and the structure has been determined. Crystal data for 1: Space group C2/c, a = 17.885(4), b = 25.230(6), c = 8.832(2) Å, β = 105.437(4)°. V = 3841(1) Å3, Z = 8 with final residuals R1 = 0.0710 and wR2 = 0.1620. The complex shows a three‐dimensional supramoleclar structure constructed with two‐dimensional infinite [Ag2(bpp)2]n sheetlike layers pillared by Ag‐Ag interactions and Ag····O (SO4) interactions in the solid state.  相似文献   

7.
The reaction of 4,4′‐bis(1,2,4‐triazol‐1‐ylmethyl)biphenyl (btmb) with silver(I) salts of BF4, NO3 and N3 led to the formation of four new silver(I) coordination polymers {[Ag(btmb)]BF4}n ( 1 ), {[Ag2(btmb)3](NO3)2(H2O)5}n ( 2 ), [Ag2(btmb)(N3)2]n ( 3 ), and [Ag(btmb)(N3)]n ( 4 ). Their coordination number varies from 2 (in 1 ) to 3 (in 2 ), 4 (in 3 ), and 5 (in 4 ). Different from the single chain structure of 1 , complex 2 displays a 1D ladder‐like double chain framework, whereas complex 3 exhibits a 2D layered architecture. Complex 4 has the same anion as complex 3 but shows a different metal‐to‐ligand ratio and a 1D double‐zigzag chain structure. Both 3 and 4 have Ag ··· Ag argentophilic interactions. The ligand btmb adopts both cis or trans configuration in the studied complexes. A trans‐ or cis‐btmb ligand link silver ions with Ag ··· Ag distances of ≈?18 and 13 Å, respectively. BF4 and NO3 are non‐coordinating anions in 1 and 2 . N3 is the bridging anion in 3 (1,3‐bridging fashion) and 4 (1,1‐bridging fashion). These findings suggest that the coordination numbers around the AgI ion correlate to the coordination abilities of anions and the btmb to silver ratio. In addition, the influence of anions on thermal stability were also investigated. This work is a good example that nicely supports the less explored field of anion‐dependent structures of complexes with non‐pyridyl ligands.  相似文献   

8.
The complexes [Ag12(Spz)12(N‐triphos)2][Ag3(Spz)3(N‐triphos)]2 · (DMF)6 ( 1 ) and [Ag18(Spz)12(N‐triphos)4(CF3CO2)6] ( 2 ) were synthesized and structurally characterized by X‐ray diffraction [HSpz = pyrazine‐2‐thiolate, N‐triphos = tris((diphenylphosphanyl)methyl)amine]. The central [Ag6] ring with chair‐conformation in 1 and the ideally octahedral [Ag6] cluster core in 2 are both stabilized by the tripodal building units of neutral [Ag3(Spz)3(N‐triphos)] compound. The Ag ··· Ag distances of the [Ag6] moieties in 1 and 2 are 3.07 and 2.81 Å, respectively, exhibiting intermetallic interactions, which can enhance the stability of [Ag6] conformations. In addition, the π ··· π interactions between parallel pyrazine rings could impose on the building and the Ag ··· Ag interactions of these Ag–S clusters.  相似文献   

9.
Four new bridged silver(I) complexes, namely [Ag22‐teda)(μ2‐fbc)2] ( 1 ), [Ag22‐1,6‐dah)2](bpdc) · 4H2O ( 2 ), [Ag22‐2‐ap)(2‐ap)(bnb)] · 0.34H2O ( 3 ), [Ag22‐pyc)2(2‐apy)2] · 0.5H2O ( 4 ), have been synthesized and characterized by elemental analysis and crystallographic methods [fbc = 4‐fluorobenzoate, teda = triethylenediamine ( 1 ); bpdc = biphenyl‐4,4′‐dicarboxylate, 1,6‐dah = 1,6‐diaminohexane ( 2 ); bnb = 3,5‐binitrobenzoate, 2‐ap = 2‐aminopyrimidine ( 3 ); pyc = 3‐pyridinecarboxylate acid, 2‐apy = 2‐aminopyridine ( 4 )]. Complex 1 contains a 1D linear chain paralleling to the c‐axis, whereas in complex 2 silver(I) atoms were bridged by the 1,6‐dah ligand into a zigzag chain, further giving a 1D ribbon by weak Ag ··· Ag interactions. Complex 3 consists of a dinuclear silver(I) [Ag22‐2‐ap)(2‐ap)(bnb)] moiety and a lattice water molecule, forming a 3D network via a number of hydrogen‐bonding interactions such as N–H ··· O, N–H ··· N and C–H ··· O hydrogen bond and other weak interactions such Ag ··· Ag, Ag ··· N, N ··· O as well as O ··· O interaction. Similar to 3 , the asymmetric unit of 4 consists of one dinuclear silver(I) [Ag22‐pyc)2(2‐apy)2] moiety and half lattice water molecule, further generating a tetranuclear silver(I) {[Ag22‐pyc)2(2‐apy)2]2 · H2O} moiety. These moieties construct a 3D supramolecular network structure of 4 through N–H ··· O, O–H ··· O and C–H ··· O hydrogen bonds as well as other weak interactions such as Ag ··· O and N ··· O interactions.  相似文献   

10.
A three‐dimensional cyano‐bridged copper(II) complex, [Cu(dien)Ag(CN)2]2[Ag2(CN)3][Ag(CN)2] ( 1 ) (dien = diethylenetriamine), has been prepared and characterized by X‐ray crystallography. Complex 1 crystallized in the monoclinic space group P21/n with a = 6.988(2), b = 17.615(6), c = 12.564(4) Å, β = 90.790(5)°. The crystal consists of cis‐[Cu(dien)]2+ units bridged by [Ag(CN)2] to form a zig‐zag chain. The Ag atoms of the free and bridging [Ag(CN)2] link together to form additional infinite zig‐zag chains with short Ag···Ag distances. The presence of Ag···Ag interactions effectively increases the dimensionality from a 1‐D chain to a 3‐D coordination polymer.  相似文献   

11.
Assembly of [Ag(CN)2]^- units with M(Ⅱ)-diamine complex cations [Cu(LN-N)2]^2+, where LN-N represents L2-diaminopropane (pn) and ethylenediamine (en), afforded two complexes, [Cu(pn)2][Ag2(CN)4] (1) and [Cu(en)2][Ag3(CN)5] (2), which were characterized by elemental analysis, IR, UV-Vis and ESR spectra. Single crystal X-ray analyses show that these complexes have 2D and 3D architectures through silver-silver interactions and other weak interactions. The luminescence behaviors of the two complexes were also studied by means of emission spectra.  相似文献   

12.
Materials having both magnetic and catalytic properties have shown great potential for practical applications. Here, a reduced graphene oxide/iron oxide/silver nanohybrid (rGO/Fe3O4/Ag NH) ternary material was prepared by green synthesis of Ag on pre‐synthesized rGO/Fe3O4. The as‐prepared rGO/Fe3O4/Ag NH was characterized using Fourier transform infrared spectroscopy, X‐ray diffractometry, Raman spectroscopy, vibrating sample magnetometry, transmission electron microscopy and energy‐dispersive X‐ray spectroscopy. rGO sheets were covered with Fe3O4 (8–16 nm) and Ag (18–40 nm) nanoparticles at high densities. The mass percentages were 13.47% (rGO), 62.52% (Fe3O4) and 24.01% (Ag). rGO/Fe3O4/Ag NH exhibited superparamagnetic behavior with high saturated magnetization (29 emu g−1 at 12 kOe), and efficiently catalyzed the reduction of 4‐nitrophenol (4‐NP) with a rate constant of 0.37 min−1, comparable to those of Ag‐based nanocatalysts. The half‐life of 4‐NP in the presence of rGO/Fe3O4/Ag NH was ca 1.86 min. rGO/Fe3O4/Ag NH could be magnetically collected and reused, and retained a high conversion efficiency of 94.4% after the fourth cycle. rGO/Fe3O4/Ag NH could potentially be used as a magnetically recoverable catalyst in the reduction of 4‐NP and environmental remediation.  相似文献   

13.
The reaction of AgNO3 and sulfobenzoate with neutral ligands led to the formation of three complexes, {[Ag2(4‐sb)(Ph3P)2(3‐apy)] · (H2O)}n ( 1 ), {[Ag(PPh3)(2‐apy)] · [Ag(PPh3)(3‐sb)] · (H2O)}n ( 2 ) and [Ag(PPh3)(Hdpa)(4‐Hsb)] ( 3 ) (4‐H2sb = 4‐sulfobenzoic acid, PPh3 = triphenylphosphine, 3‐apy = 3‐aminopyridine, 2‐apy = 2‐aminopyridine, 3‐H2sb = 3‐sulfobenzoic acid, Hdpa = 2,2′‐dipyridylamine) Complex 1 is a 2D sandwich‐like polymer. Complex 2 is a cation‐anion species and has a 1D polymer structure. Complex 3 is a monomer. Complexes 1 – 3 contain the Ag‐PPh3 unit and such unit largely hinders the Ag–Ag, π ··· π, Ag ··· π, and Ag ··· C interactions. The experimental results indicated that these three complexes have weaker conductivities than those corresponding silver complexes having abundant weak interactions, especially π ··· π and Ag–Ag interactions, illustrating that the cation‐anion species having potential ability of charge transfer can largely promote the conductivity property.  相似文献   

14.
Catalytic direct dehydrogenation of methanol to formaldehyde was carried out over Ag‐SiO2‐MgO‐Al2O3 catalysts prepared by sol‐gel method. The optimal preparation mass fractions were determined as 8.3% MgO, 16.5% Al2O3 and 20% silver loading. Using this optimum catalyst, excellent activity and selectivity were obtained. The conversion of methanol and the selectivity to formaldehyde both reached 100%, which were much higher than other previously reported silver supported catalysts. Based on combined characterizations, such as X‐ray diffraction (XRD), scanning electronic microscopy (SEM), diffuse reflectance ultraviolet‐visible spectroscopy (UV‐Vis, DRS), nitrogen adsorption at low temperature, temperature programmed desorption of ammonia (NH3‐TPD), desorption of CO2 (CO2‐TPD), etc., the correlation of the catalytic performance to the structural properties of the Ag‐SiO2‐ MgO‐Al2O3 catalyst was discussed in detail. This perfect catalytic performance in the direct dehydrogenation of methanol to formaldehyde without any side‐products is attributed to its unique flower‐like structure with a surface area less than 1 m2/g, and the strong interactions between neutralized support and the nano‐sized Ag particles as active centers.  相似文献   

15.
To investigate the influence of the non‐covalent interactions, such as hydrogen‐bonding, π–π packing and d10–d10 interactions in the supramolecular motifs, three cyanido‐bridged heterobimetallic discrete complexes {Mn(bipy)2(H2O)[Ag(CN)2]}[Ag(CN)2] ( 1 ), {Mn(phen)2(H2O)[Au(CN)2]}2[Au(CN)2]2 · 4H2O ( 2 ), and {Cd(bipy)2(H2O)[Au(CN)2]}[Au(CN)2] ( 3 ) (bipy = 2,2′‐bipyridine, and phen = 1,10‐phenanthroline), which are based on dicyanidometallate(I) groups with 1:2 stoichiometry of metal ions and 2,2′‐bipyridyl‐like co‐ligands were synthesized and structurally characterized. In compound 1 , hydrogen bonding and π–π interactions governed the supramolecular contacts. In compound 2 , the incorporation of aurophilic, hydrogen bonding and π–π interactions result in a 3D supramolecular network. In compound 3 , hydrogen bonding and π–π stacking interactions result in a 2D supramolecular layer. In the three complexes, hydrogen‐bonding, π–π packing and/or d10–d10 interactions can play important roles in increasing the dimensionality of supramolecular assemblies.  相似文献   

16.
A novel infinite one‐dimensional silver cylinder, namely poly[μ‐ethylenediamine‐μ5‐(2‐sulfanidylbenzoato)‐μ4‐(2‐sulfanidylbenzoato)‐tetrasilver(I)], [Ag4(C7H4O2S)2(C2H8N2)]n, has been synthesized by one‐pot reaction of equivalent molar silver nitrate and 2‐mercaptobenzoic acid (H2mba) in the presence of ethylenediamine (eda). One Ag atom is located in an AgS2NO four‐coordinated tetrahedral geometry, two other Ag atoms are in an AgS2O three‐coordinated T‐shaped geometry and the fourth Ag atom is in an AgSNO coordination environment. The two mba ligands show two different binding modes. The μ2N:N′‐eda ligand, acting as a bridge, combines with mba ligands to extend the AgI ions into a one‐dimensional silver cylinder incorporating abundant Ag...Ag interactions ranging from 2.9298 (11) to 3.2165 (13) Å. Interchain N—H...O hydrogen bonds extend the one‐dimensional cylinder into an undulating two‐dimensional sheet, which is further packed into a three‐dimensional supramolecular framework by van der Waals interactions; no π–π interactions were observed in the crystal structure.  相似文献   

17.
The title compound, {[Ag(C6H7AsNO3)(C18H15P)]·H2O}n, has been synthesized from the reaction of 4‐aminophenylarsonic acid with silver nitrate, in aqueous ammonia, with the addition of triphenylphosphane (PPh3). The AgI centre is four‐coordinated by one amino N atom, one PPh3 P atom and two arsonate O atoms, forming a severely distorted [AgNPO2] tetrahedron. Two AgI‐centred tetrahedra are held together to produce a dinuclear [Ag2O2N2P2] unit by sharing an O–O edge. 4‐Aminophenylarsonate (Hapa) adopts a μ3‐κ3N:O:O‐tridentate coordination mode connecting two dinuclear units, resulting in a neutral [Ag(Hapa)(PPh3)]n layer lying parallel to the (10) plane. The PPh3 ligands are suspended on both sides of the [Ag(Hapa)(PPh3)]n layer, displaying up and down orientations. There is an R22(8) hydrogen‐bonded dimer involving two arsonate groups from two Hapa ligands related by a centre of inversion. Additionally, there are hydrogen‐bonding interactions involving the solvent water molecules and the arsonate and amine groups of the Hapa ligands, and weak π–π stacking interactions within the [Ag(Hapa)(PPh3)]n layer. These two‐dimensional layers are further assembled by weak van der Waals interactions to form the final architecture.  相似文献   

18.
Two diamagnetic‐metal nitronyl nitroxide radical complexes with dicyanoargentate(I) bridges M(NIT4Py)2[Ag(CN)2]2 (M= Zn, Cd) were synthesized. X‐ray crystallography reveals that the two compounds are isomorphous, which crystallize in the triclinic space group. Their structures consist of infinite chains of M(NIT4Py)2 units linked by [Ag(CN)2]? μ2‐bridging ligands. The magnetic measurements showed that the χMT values are nearly constants at higher temperature for both complexes. The sharp decreasing of χMT values at lower temperature are related to intermolecular antiferromagnetic interactions, which result from the shortest interchain contacts of nitroxide groups in the crystals.  相似文献   

19.
The syntheses, structures, and chemotherapeutic activities of Ag(I)‐, Au(I)‐, and Ru(II)‐complexes ligated to a novel N‐heterocyclic carbene ligand, 2‐(4‐nitrophenyl)imidazo[1,5‐a]pyridin‐2‐ylidene ( 1 ), are described. The corresponding complexes, [Ag( 1 )2][PF6], [Au( 1 )2][PF6] ( 3 ), and [Ru( 1 )(p‐cymene)Cl][PF6] ( 4 ), were prepared using convenient transmetallation chemistry and characterized using a range of spectroscopic and analytical techniques. X‐ray crystallography revealed that complexes 2 and 3 adopted linear structures whereas 4 exhibited a prototypical “piano‐stool”‐like geometry; the structural assignments were further supported by DFT calculations. A series of in vitro studies revealed that while the aforementioned Ag(I), Au(I) and Ru(II) complexes exhibited significant cytotoxicities against the human colon adenocarcinoma (HCT 116), lung cancer (A549), and breast cancer (MCF7) cell lines, the Ru derivative was most prominent.  相似文献   

20.
In the present work, the two‐dimensional (2D) polymer poly[[μ4‐2‐(4‐nitrobenzenesulfonamido)benzoato‐κ4O1:O1:O1′:N6]silver(I)] (AgL), [Ag(C13H9N2O6S)]n, was obtained from 2‐(4‐nitrobenzenesulfonamido)benzoic acid (HL), C13H10N2O6S. FT–IR, 1H and 13C{1H} NMR spectroscopic analyses were used to characterize both compounds. The crystal structures of HL and AgL were determined by single‐crystal X‐ray diffraction. In the structure of HL, O—H…O hydrogen bonds between neighbouring molecules result in the formation of dimers, while the silver(I) complex shows polymerization associated with the O atoms of three distinct deprotonated ligands (L?). Thus, the structure of the Ag complex can be considered as a coordination polymer consisting of a one‐dimensional linear chain, constructed by carboxylate bridging groups, running parallel to the b axis. Neighbouring polymeric chains are further bridged by Ag—C monohapto contacts, resulting in a 2D framework. Fingerprint analysis of the Hirshfeld surfaces show that O…H/H…O hydrogen bonds are responsible for the most significant contacts in the crystal packing of HL and AgL, followed by the H…H and O…C/C…O interactions. The Ag…Ag, Ag…O/O…Ag and Ag…C/C…Ag interactions in the Hirshfeld surface represent 12.1% of the total interactions in the crystal packing. Studies of the interactions of the compounds with human serum albumin (HSA) indicated that both HL and AgL interact with HSA.  相似文献   

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