catena‐Poly[[[(iminodiacetato‐κO)silver(I)]‐μ3‐2‐aminopyrimidine‐κ3N1:N2:N3] monohydrate]: a one‐dimensional silver(I) coordination polymer with mixed ligands

The title compound, {[Ag(C₄H₆NO₄)(C₄H₅N₃)]·H₂O}_n, was synthesized by the reaction of silver(I) nitrate with 2‐aminopyrimidine and iminodiacetic acid. X‐ray analysis reveals that the crystal structure contains a one‐dimensional ladder‐like Ag^I coordination polymer and that N—H...O and O—H...O hydrogen bonding results in a three‐dimensional network. The Ag^I centre is four‐coordinated by three N atoms from three different 2‐aminopyrimidine ligands and one O atom from one iminodiacetate ligand. Comparison of the structural features with previous findings suggests that the existence of a second ligand plays an important role in the construction of such polymer frameworks.     

Poly[bis(μ2‐2‐aminopyrazine‐κ2N1:N4)(μ2‐nitrato‐κ2O:O)(nitrato‐κ2O,O′)disilver(I)]: an achiral two‐dimensional coordination polymer forming chiral crystals

The solution reaction of AgNO₃ and 2‐aminopyrazine (apyz) in a 1:1 ratio gives rise to the title compound, [Ag₂(NO₃)₂(C₄H₅N₃)₂]_n, (I), which possesses a chiral crystal structure. In (I), both of the crystallographically independent Ag^I cations are coordinated in tetrahedral geometries by two N atoms from two apyz ligands and two O atoms from nitrate anions; however, the Ag^I centers show two different coordination environments in which one is coordinated by two O atoms from two different symmetry‐related nitrate anions and the second is coordinated by two O atoms from a single nitrate anion. The crystal structure consists of one‐dimensional Ag^I–apyz chains, which are further extended by μ₂‐κ²O:O nitrate anions into a two‐dimensional (4,4) sheet. N—H...O and C_apyz—H...O hydrogen bonds connect neighboring sheets to form a three‐dimensional supramolecular framework.     

The coordination polymer poly[(μ3‐3‐aminocarbonylpyrazine‐2‐carboxylato‐κ3N1:O2:O2′)silver(I)]

The title compound, [Ag(C₆H₄N₃O₃)]_n or [Ag(pyzca)]_n (where pyzca is 3‐aminocarbonylpyrazine‐2‐carboxylate), (I), was obtained by silver‐catalysed partial hydrolysis of pyrazine‐2,3‐dicarbonitrile in aqueous solution. The compound has a distorted trigonal–planar coordination geometry around the Ag^I ion, with each ligand bridging three Ag^I ions to form a one‐dimensional strand of molecules parallel to the b axis. An extensive hydrogen‐bond pattern connects these strands to form a three‐dimensional network of mog topology.     

catena‐Poly­[[(benzoato‐κO)silver(I)]‐μ‐2‐amino­pyrimidine‐κ2N1:N3]

The title complex, [Ag(C₇H₅O₂)(C₄H₅N₃)]_n, is a polymer based on a mononuclear silver(I)‐centered fragment. The Ag^I atom is trigonally coordinated by two N atoms from two 2‐­amino­pyrimidine ligands and one O atom from one benzoate anion, giving zigzag polymeric chains with an [–Ag—N—C—N–]_n backbone running along the a axis. It is proposed that intermolecular hydrogen bonding drives the formation of the chain polymer.     

catena‐Poly­[[(di‐2‐pyridyl­amine)­silver(I)]‐μ‐nicotinato] and catena‐poly­[[(di‐2‐pyridyl­amine)silver(I)]‐μ‐2,6‐di­hydroxy­benzoato]

In catena‐poly­[[(di‐2‐pyridyl­amine‐κ²N,N′)silver(I)]‐μ‐nico­tinato‐κ²N:O], [Ag(C₆H₄NO₂)(C₁₀H₉N₃)]_n, the Ag^I atom is tetracoordinated by two N atoms from the di‐2‐pyridyl­amine (BPA) ligand [Ag—N = 2.3785 (18) and 2.3298 (18) Å] and by one N atom and one carboxyl­ate O atom from nicotinate ligands [Ag—N = 2.2827 (15) Å and Ag—O = 2.3636 (14) Å]. Bridging by nicotinate N and O atoms generates a polymeric chain structure, which extends along [100]. The carboxyl O atom not bonded to the Ag atom takes part in an intrachain C—H⋯O hydrogen bond, further stabilizing the chain. Pairs of chains are linked by N—H⋯O hydrogen bonds to generate ribbons. There are no π–π interactions in this complex. In catena‐poly­[[(di‐2‐pyridyl­amine‐κ²N,N′)silver(I)]‐μ‐2,6‐di­hydroxy­benzoato‐κ²O¹:O²], [Ag(C₇H₅O₄)(C₁₀H₉N₃)]_n, the Ag^I atom has a distorted tetrahedral coordination, with three strong bonds to two pyridine N atoms from the BPA ligand [Ag—N = 2.286 (5) and 2.320 (5) Å] and to one carboxyl­ate O atom from the 2,6‐di­hydroxy­benzoate ligand [Ag—O = 2.222 (4) Å]; the fourth, weaker, Ag‐atom coordination is to one of the phenol O atoms [Ag⋯O = 2.703 (4) Å] of an adjacent moiety, and this interaction generates a polymeric chain along [100]. Pairs of chains are linked about inversion centers by N—H⋯O hydrogen bonds to form ribbons, within which there are π–π interactions. The ribbons are linked about inversion centers by pairs of C—H⋯O hydrogen bonds and additional π–π interactions between inversion‐related pairs of 2,6‐di­hydroxy­benzoate ligands to generate a three‐dimensional network.     

catena‐Poly[[bis(nicotinamide‐κN1)copper(I)]‐μ‐thiocyanato‐κ2N:S]

The Cu^I cations in the title compound, [Cu(NCS)(C₆H₆N₂O)₂]_n, are coordinated by N atoms from each of two mirror‐related nicotin­amide ligands, as well as by one N atom of one thio­cyanate ligand and one S atom of a symmetry‐related thio­cyanate ligand, within a slightly distorted tetrahedron. The Cu^I cations and the thio­cyanate anions are located on a crystallographic mirror plane and the nicotin­amide ligands occupy general positions. The Cu^I cations are connected by the thio­cyanate anions to form chains in the direction of the crystallographic a axis. These chains are connected by hydrogen bonds between the amide H atoms and the O atoms of adjacent nicotin­amide ligands, to give a three‐dimensional structure.     

An unusual chain cadmium(II) coordination polymer: catena‐poly[[(2,2′‐bipyridyl‐κ2N,N′)cadmium(II)]‐di‐μ‐chlorido‐[(2,2′‐bipyridyl‐κ2N,N′)cadmium(II)]‐di‐μ‐thiocyanato‐κ2N:S;κ2S:N]

The title complex, [CdCl(NCS)(C₁₀H₈N₂)]_n, represents an unusual Cd^II 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 Cd^II 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 Cd^II 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.     

A two‐dimensional silver(I) coordination polymer constructed from 4‐aminophenylarsonate and triphenylphosphane: poly[[(μ3‐4‐aminophenylarsonato‐κ3N:O:O)(triphenylphosphane‐κP)silver(I)] monohydrate]

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 Ag^I 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 Ag^I‐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.     

catena‐Poly­[1,4‐diazo­niabicyclo­[2.2.2]­octane [silver(I)‐tri‐μ‐thio­cyanato‐κ6S:S]]

The title compound, {(C₆H₁₄N₂)[Ag(NCS)₃]}_n, is a polymeric silver(I) complex. The Ag^I atom is hexacoordinated by the S atoms of six thio­cyanate anions, with each thio­cyanate S atom acting in a bridging mode to link the Ag atoms together. The unique Ag^I atom lies at a cell origin and has crystallo­graphically imposed symmetry. The diazonia[2.2.2]octane molecule lies about a site with imposed symmetry with the unique N atom on a threefold axis. The S and N atoms of the thio­cyanate ligands sit on a mirror plane and a threefold axis, respectively. The crystal structure consists of one‐dimensional chains, which are stabilized by N—H⋯N hydrogen bonds to form a three‐dimensional network.     

A novel one‐dimensional metal–organic framework with a μ‐cyanido‐argentate group: catena‐poly[[(5,5′‐dimethyl‐2,2′‐bipyridyl‐κ2N,N′)silver(I)]‐μ‐cyanido‐κ2N:C]

The design and synthesis of metal coordination and supramolecular frameworks containing N‐donor ligands and dicyanidoargentate units is of interest due to their potential applications in the fields of molecular magnetism, catalysis, nonlinear optics and luminescence. In the design and synthesis of extended frameworks, supramolecular interactions, such as hydrogen bonding, π–π stacking and van der Waals interactions, have been exploited for molecular recognition associated with biological activity and for the engineering of molecular solids.The title compound, [Ag(CN)(C₁₂H₁₂N₂)]_n, crystallizes with the Ag^I cation on a twofold axis, half a cyanide ligand disordered about a centre of inversion and half a twofold‐symmetric 5,5′‐dimethyl‐2,2′‐bipyridine (5,5′‐dmbpy) ligand in the asymmetric unit. Each Ag^I cation exhibits a distorted tetrahedral geometry; the coordination environment comprises one C(N) atom and one N(C) atom from substitutionally disordered cyanide bridging ligands, and two N atoms from a bidentate chelating 5,5′‐dmbpy ligand. The cyanide ligand links adjacent Ag^I cations to generate a one‐dimensional zigzag chain. These chains are linked together via weak nonclassical intermolecular interactions, generating a two‐dimensional supramolecular network.     

Powder study of poly[(μ2‐2,2‐dimethylpropane‐1,3‐diyl diisocyanide)‐μ2‐iodido‐silver(I)]

In order to explore the chemistry of the bidentate ligand 2,2‐dimethylpropane‐1,3‐diyl diisocyanide and to investigate the effect of counter‐ions on the polymeric structure of (2,2‐dimethylpropane‐1,3‐diyl diisocyanide)silver(I) complexes, the title polymeric compound, [AgI(C₇H₁₀N₂)]_n, was synthesized by treatment of 2,2‐dimethylpropane‐1,3‐diyl diisocyanide with AgI. X‐ray powder diffraction studies show, as expected, a polymeric structure, similar to the very recently reported Cl⁻ and NO₃⁻ analogues [AgX(C₇H₁₀N₂)]_n (X = Cl⁻ or NO₃⁻). In the title structure, the Ag^I centre is bridged to two adjacent Ag^I neighbours by bidentate 2,2‐dimethylpropane‐1,3‐diyl diisocyanide ligands via the NC groups to form [Ag{CNCH₂C(CH₃)₂CH₂NC}]_n chains. The iodide counter‐ions crosslink the Ag^I centres of the chains to form a two‐dimensional polymeric {[Ag{CNCH₂C(CH₃)₂CH₂NC}]I}_n network. This study also shows that this bidentate ligand forms similar polymeric structures on treatment with AgX, regardless of the nature of the counter‐ion X⁻, and also has a strong tendency to form polymeric complexes rather than dimeric or trimeric ones.     

catena‐Poly[[silver(I)‐μ‐[9,10‐bis(1H‐benzimidazol‐1‐ylmethyl)anthracene]‐κ2N3:N3′] bis(nitrato‐κO)silver(I)]

Yellow needle‐shaped crystals of the title compound, {[Ag(C₃₀H₂₂N₄)][Ag(NO₃)₂]}_n, were obtained by the reaction of AgNO₃ and 9,10‐bis(benzimidazol‐1‐ylmethyl)anthracene (L) in a 2:1 ratio. The asymmetric unit consists of two Ag^I cations, one half L ligand and one nitrate anion. One Ag^I cation occupies a crystallographic inversion centre and links two N‐atom donors of two distinct L ligands to form an infinite one‐dimensional coordination polymer. The second Ag^I cation lies on a crystallographic twofold axis and is coordinated by two O‐atom donors of two nitrate anions to form an [Ag(NO₃)₂]⁻ counter‐ion. The polymeric chains are linked into a supramolecular framework via weak Ag...O [3.124 (5) Å] and Ag...π (2.982 Å) interactions (π is the centroid of an outer anthracene benzene ring). The π interactions contain two short Ag...C contacts [2.727 (6) and 2.765 (6) Å], which can be considered to define Ag–η²‐anthracene bonding interactions. In comparison with a previously reported binuclear Ag^I complex [Du, Hu, Zhang, Zeng & Bu (2008). CrystEngComm, 10 , 1866–1874], this new one‐dimensional coordination polymer was obtained by changing the metal–ligand ratio during the synthesis.     

Poly[μ2‐(N‐hydroxypyridine‐2‐carboxamidine)‐μ2‐nitrato‐silver(I)]

In the title complex, [Ag(NO₃)(C₆H₇N₃O)]_n or [Ag(NO₃)(pyaoxH₂)] (pyaoxH₂ is N‐hydroxypyridine‐2‐carboxamidine), the Ag⁺ ion is bridged by the pyaoxH₂ ligands and nitrate anions, giving rise to a two‐dimensional molecular structure. Each pyaoxH₂ ligand coordinates to two Ag⁺ ions using its pyridyl and carboxamidine N atoms, and the OH and the NH₂ groups are uncoordinated. Each nitrate anion uses two O atoms to coordinate to two Ag⁺ ions. The Ag...Ag separation via the pyaoxH₂ bridge is 2.869 (1) Å, markedly shorter than that of 6.452 (1) Åvia the nitrate bridge. The two‐dimensional structure is fishscale‐like, and can be described as pyaoxH₂‐bridged Ag₂ nodes that are further linked by nitrate anions. Hydrogen bonding between the amidine groups and the nitrate O atoms connects adjacent layers into a three‐dimensional network.     

A stair‐like two‐dimensional silver(I) coordination polymer of N′‐(3‐cyanobenzylidene)nicotinohydrazide

The structure of the title compound, poly[[[μ₃‐N′‐(3‐cyanobenzylidene)nicotinohydrazide]silver(I)] hexafluoroarsenate], {[Ag(C₁₄H₁₀N₄O)](AsF₆)}_n, at 173 K exhibits a novel stair‐like two‐dimensional layer and a three‐dimensional supramolecular framework through C—H...Ag hydrogen bonds. The Ag^I cation is coordinated by three N atoms and one O atom from N′‐(3‐cyanobenzylidene)nicotinohydrazide (L) ligands, resulting in a distorted tetrahedral coordination geometry. The organic ligand acts as a μ₃‐bridging ligand through the pyridyl and carbonitrile N atoms and deviates from planarity in order to adapt to the coordination geometry. Two ligands bridge two Ag^I cations to construct a small 2+2 Ag₂L₂ ring. Four ligands bridge one Ag^I cation from each of four of these small rings to form a large grid. An interesting stair‐like two‐dimensional (3,6)‐net is formed through Ag^I metal centres acting as three‐connection nodes and through L molecules as tri‐linkage spacers.     

Monoclinic and triclinic concomitant polymorphs of di‐μ‐pyridazine‐1κ2N:2κ2N′‐bis­[(saccharinato)silver(I)]

Crystallization of the title compound, di‐μ‐pyridazine‐1κ²N:2κ²N′‐bis­[(2,3‐dihydro‐3‐oxobenzisosulfonazolato‐κN)silver(I)], [Ag₂(C₇H₄NO₃S)₂(C₄H₄N₂)₂], from acetonitrile yields both monoclinic, (I), and triclinic, (II), polymorphs. In both forms, the silver(I) ions have a slightly distorted trigonal AgN₃ coordination geometry and are doubly bridged by two neutral pyridazine (pydz) ligands, generating a centrosymmetric dimeric structure. The saccharinate (sac) ligands are N‐coordinated. The dihedral angles between the sac and pydz rings are 8.43 (7) and 7.94 (8)° in (I) and (II), respectively, suggesting that the dimeric mol­ecule is nearly flat. The bond geometry is similar in both polymorphs. In (I), the dimers inter­act with each other via aromatic π_sac–π_pydz stacking inter­actions, forming two‐dimensional layers, which are further crosslinked by weak C—H⋯O inter­actions. Compound (II) exhibits similar C—H⋯O and π–π inter­actions, but additional C—H⋯π and π⋯Ag inter­actions help to stabilize the packing of the dimers.     

Supramolecular framework in catena‐poly[[(nitrato‐κO)silver(I)]‐μ‐(R,S)‐2‐(pyridin‐4‐ylsulfinyl)pyrimidine‐κ3N,O:N′]

In the title complex, [Ag(NO₃)(C₉H₇N₃OS)]_n, η¹:η¹:η¹:μ₂‐bridging 2‐(pyridin‐4‐ylsulfinyl)pyrimidine (pypmSO) ligands with opposite chiralities are alternately arranged to link the Ag^I cations through two N atoms and one sulfinyl O atom of each ligand, leading to an extended zigzag coordination chain structure along the [01] direction. An FT–IR spectroscopic study shows a decreased stretching frequency for the η¹‐O‐bonded S=O group compared with that of the free ligand. The parallel chains are arranged and interconnected via O(S=O)...π(pyridine/pyrimidine) and C—H(pyridine)...O(NO₃⁻) interactions to furnish a layer almost parallel to the ac plane. Along the b axis, the layers are stacked and stabilized through anion(NO₃⁻)...π(pyrimidine) interactions to form a three‐dimensional supramolecular framework. The ligand behaviour of the new diheterocyclic sulfoxide and the unconventional O(S=O)...π(pyridine/pyrimidine) and anion(NO₃⁻)...π(pyrimidine) interactions in the supramolecular assembly of the title complex are presented.     

catena‐Poly[[bis[5‐(4‐pyridyl‐κN)‐2‐(2‐pyridylmethylsulfanyl)‐1,3,4‐oxadiazole]cadmium(II)]‐di‐μ‐thiocyanato‐κ2N:S;κ2S:N]

The title compound, [Cd(NCS)₂(C₁₃H₁₀N₄OS)₂]_n, contains SCN⁻ anions acting as end‐to‐end bridging ligands which utilize both S and N atoms to link cadmium(II) centers into one‐dimensional double chains. The multidentate 5‐(4‐pyridyl)‐2‐(2‐pyridylmethylsulfanyl)‐1,3,4‐oxadiazole ligands behave as monodentate terminal ligands, binding metal centers only through the N atoms of the 4‐pyridyl groups. Two types of eight‐membered rings are formed by two SCN⁻ anions bridging Cd^II centers, viz. planar and chair conformation, which are alternately disposed along the same chain. Finally, chains define a two‐dimensional array through two different interchain π–π stacking interactions.     

A one‐dimensional silver(I) coordination polymer based on 5‐methyl‐1,3,4‐thiadiazol‐2‐amine and pyridine‐2,3‐dicarboxylate

The bifunctional pyridine‐2,3‐dicarboxylic acid (H₂pdc) ligand has one N atom and four O atoms, which could bind more than one Ag^I centre with diverse binding modes. A novel infinite one‐dimensional Ag^I coordination polymer, namely catena‐poly[[silver(I)‐(μ₂‐pyridine‐2,3‐dicarboxylato‐κ²N :O ³)‐silver(I)‐tris(μ₂‐5‐methyl‐1,3,4‐thiodiazol‐2‐amine‐κ²N :N ′)] monohydrate ethanol monosolvate], {[Ag₂(C₇H₃NO₄)(C₃H₅N₃S)₃]·H₂O·C₂H₅OH}_n , has been synthesized using H₂pdc and 5‐methyl‐1,3,4‐thiadiazol‐2‐amine (tda), and characterized by single‐crystal X‐ray diffraction. One Ag^I atom is located in a four‐coordinated AgN₄ tetrahedral geometry and the other Ag^I atom is in a tetrahedral AgN₃O geometry. A dinuclear Ag^I cluster formed by three tda ligands with a paddelwheel configuration is bridged by the dianionic pdc²⁻ ligand into a one‐dimensional coordination polymer. Interchain N—H…O hydrogen bonds extend the one‐dimensional chains into an undulating two‐dimensional sheet. The sheets are further packed into a three‐dimensional supramolecular framework by interchain N—H…O hydrogen bonds.     

A grid‐like two‐dimensional AgI coordination polymer: poly[[[μ3‐N′‐(4‐cyanobenzylidene)isonicotinohydrazide]silver(I)] perchlorate]

This study presents new coordinating modes of a Schiff base with three coordinating groups and an interesting two‐dimensional framework based on two types of constructing units. In the title compound, {[Ag(C₁₄H₁₀N₄O)]ClO₄}_n, the Ag^I ion is coordinated by three N atoms and one O atom from three different N′‐(4‐cyanobenzylidene)isonicotinohydrazide (L) ligands, forming a primary distorted square‐planar coordination geometry. Two ligands each bridge two metal centres through one carbonitrile N atom in a monodentate mode and the hydrazide N and O atoms in a bidentate mode to form a small centrosymmetric (2+2)‐Ag₂L₂ ring as a principal constructing unit. The pyridyl N atoms from four ligands in four of these small rings coordinate to Ag atoms in adjacent rings to form a large hexanuclear silver grid. A two‐dimensional framework of rectangular grids is constructed from these small rings and large grids. Two perchlorate anions are located in each large grid and are bound to the grid by N—H...O hydrogen bonding. Crosslinking between the layers is achieved through long Ag...O interactions between the perchlorate anions and Ag atoms in adjacent layers.     

Silver(I) complexes of 2‐(2‐amino­eth­yl)pyridine: nitrate and perchlorate salts of bis­[μ‐2‐(2‐amino­eth­yl)pyridine‐κ2N:N′]disilver(I)

2‐(2‐Amino­eth­yl)pyridine (2‐aep, C₇H₁₀N₂) acts as a bridging ligand in bis­[μ‐2‐(2‐amino­eth­yl)pyridine‐κ²N:N′]disilver(I) dinitrate, [Ag₂(2‐aep)₂](NO₃)₂, and bis­[μ‐2‐(2‐amino­eth­yl)­pyridine‐κ²N:N′]disilver(I) diperchlorate, [Ag₂(2‐aep)₂](ClO₄)₂. Both salts contain the dinuclear [Ag₂(2‐aep)₂]²⁺ cation, which possesses a crystallographic inversion center. The Ag⋯Ag distance is 3.1163 (5) Å for the nitrate and 3.0923 (3) Å for the perchlorate salt, and may indicate a weak d¹⁰–d¹⁰ inter­action in each case. Essentially linear coordination of the Ag^I atom is perturbed by weak coordination to the anionic O atoms. These latter inter­actions organize the dinuclear cations into one‐dimensional polymeric chains in the crystals of the two salts.