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 novel two‐dimensional coordination polymer: poly[diaquatetra‐μ2‐chlorido‐[μ2‐2,2′‐(piperazine‐1,4‐diium‐1,4‐diyl)diacetate]dicadmium(II)]

In the crystal structure of the title two‐dimensional metal–organic polymeric complex, [Cd₂Cl₄(C₈H₁₄N₂O₄)(H₂O)₂]_n, the asymmetric unit contains a crystallographically independent Cd^II cation, two chloride ligands, an aqua ligand and half a 2,2′‐(piperazine‐1,4‐diium‐1,4‐diyl)diacetate (H₂PDA) ligand, the piperazine ring centroid of which is located on a crystallographic inversion centre. Each Cd^II centre is six‐coordinated in an octahedral environment by an O atom from an H₂PDA ligand and an O atom from an aqua ligand in a trans disposition, and by four chloride ligands arranged in the plane perpendicular to the O—Cd—O axis. The complex forms a two‐dimensional layer polymer containing [CdCl₂]_n chains, which are interconnected into an extensive three‐dimensional hydrogen‐bonded network by C—H...O, C—H...Cl and O—H...O hydrogen bonds.     

A three‐dimensional cadmium(II) coordination polymer: poly[[[μ‐4,4′‐(propane‐1,3‐diyl)dipyridine‐κ2N:N](μ‐3,3′‐thiodipropionato‐κ3O,O′:O)cadmium(II)] monohydrate]

In the title coordination polymer, {[Cd(C₆H₈O₄S)(C₁₃H₁₄N₂)]·H₂O}_n, the Cd^II atom displays a distorted octahedral coordination, formed by three carboxylate O atoms and one S atom from three different 3,3′‐thiodipropionate ligands, and two N atoms from two different 4,4′‐(propane‐1,3‐diyl)dipyridine ligands. The Cd^II centres are bridged through carboxylate O atoms of 3,3′‐thiodipropionate ligands and through N atoms of 4,4′‐(propane‐1,3‐diyl)dipyridine ligands to form two different one‐dimensional chains, which intersect to form a two‐dimensional layer. These two‐dimensional layers are linked by S atoms of 3,3′‐thiodipropionate ligands from adjacent layers to form a three‐dimensional network.     

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.     

catena‐Poly[[(2,2′‐biimidazole‐κ2N,N′)chloro­copper(II)]‐μ‐chloro]

In the polymeric title compound, [CuCl₂(C₆H₆N₄)]_n, each Cu^II ion is five‐coordinated by four basal atoms (two N atoms from a 2,2′‐biimidazole mol­ecule and two Cl⁻ anions) and one axial Cl⁻ anion, in a distorted square‐pyramidal coordination geometry. Cl⁻ anions bridge the {Cu(C₆H₆N₄)Cl} units into one‐dimensional linear chains, which are reinforced by π–π inter­actions. Adjacent linear chains are linked by N—H⋯Cl hydrogen bonds, resulting in a grid layer. The hydrogen‐bonding pattern can be described in graph‐set notation as C(9)R(9)R(14). This study extends our knowledge of the multifunctional properties of the 2,2′‐biimidazole ligand and of the coordination stereochemistry of copper(II).     

Bis{μ‐3‐[3‐(2‐pyridyl)pyrazol‐1‐ylmethyl]pyridine}disilver(I) bis(trifluoromethanesulfonate): effect of counter‐anions on the self‐assembly of coordination complexes

As part of a study on the effect of different counter‐anions on the self‐assembly of coordination complexes, a new dinuclear Ag^I complex, [Ag₂(C₁₄H₁₂N₄)₂](CF₃SO₃)₂, with the 3‐[3‐(2‐pyridyl)pyrazol‐1‐ylmethyl]pyridine (L) ligand was obtained through the reaction of L with AgCF₃SO₃. In this complex, each Ag^I center in the centrosymmetric dinuclear complex cation is coordinated by two pyridine and one pyrazole N‐atom donor of two inversion‐related L ligands in a trigonal planar geometry. This forms a unique box‐like cyclic dimer with an intramolecular nonbonding Ag...Ag separation of 6.379 (7) Å. Weak Ag...CF₃SO₃ and C—H...X (X = O and F) hydrogen‐bonding interactions, together with π–π stacking interactions, link the complex cations along the [001] and [10] directions, respectively, generating two different one‐dimensional chains and then an overall two‐dimensional network of the complex running parallel to the (110) plane. Comparison of the structural differences with previous findings suggests that the presence of different counter‐anions plays an important role in the construction of such supramolecular frameworks.     

catena‐Poly[bis[1‐chloromethyl‐1,4‐diazoniabicyclo[2.2.2]octane] [cadmium(II)‐tri‐μ‐chlorido‐[chloridocadmium(II)]‐di‐μ‐chlorido‐[chloridocadmium(II)]‐tri‐μ‐chlorido] tetrahydrate]

The title compound, {(C₇H₁₅N₂Cl)₂[Cd₃Cl₁₀]·4H₂O}_n, consists of 1‐chloromethyl‐1,4‐diazoniabicyclo[2.2.2]octane dications, one‐dimensional inorganic chains of {[Cd₃Cl₁₀]⁴⁻} anions and uncoordinated water molecules. Each of the two independent Cd^II ions, one with site symmetry 2/m and the other with site symmetry m, is octahedrally coordinated by chloride ions (two with site symmetry m and one with site symmetry 2), giving rise to novel polymeric zigzag chains of corner‐sharing Cd‐centred octahedra parallel to the c axis. The organic cations, bisected by mirror planes that contain the two N atoms, three methylene C atoms and the Cl atom, are ordered. Hydrogen bonds (O—H...Cl and O—H...O) between the water molecules (both with O atoms in a mirror plane) and the chloride anions of neighbouring chloridocadmate chains form a three‐dimensional supramolecular network.     

catena‐Poly[[disilver(I)(Ag—Ag)‐bis[μ‐1,1′‐(butane‐1,4‐diyl)diimidazole‐κ2N3:N3′]] bis(perchlorate)]: a double helix stabilized by ligand‐unsupported argentophilic interactions

The title compound, {[Ag₂(C₁₀H₁₄N₄)₂](ClO₄)₂}_n, is a one‐dimensional coordination polymer formed by Ag^I atoms linearly bridged by 1,1′‐(butane‐1,4‐diyl)diimidazole molecules. The chains have a helical arrangement and pairs of chains are held together by the rarely reported ligand‐unsupported Ag—Ag interaction [2.966 (1) Å], which results in a double‐helix structure. The double helix contains twisted 24‐membered metallomacrocycles, which are composed of four Ag atoms and two ligands. The Ag atoms lie on twofold axes.     

Chlorido(dimethyl 2,2′‐bipyridine‐4,4′‐dicarboxylate‐κ2N,N′)(η5‐pentamethylcyclopentadienyl)rhodium(III) chloride 1‐hydroxypyrrolidine‐2,5‐dione disolvate

The title complex, [Rh(C₁₀H₁₅)Cl(C₁₄H₁₂N₂O₄)]Cl·2C₄H₅NO₃, has been synthesized by a substitution reaction of the precursor [bis(2,5‐dioxopyrrolidin‐1‐yl) 2,2′‐bipyridine‐4,4′‐dicarboxylate]chlorido(pentamethylcyclopentadienyl)rhodium(III) chloride with NaOCH₃. The Rh^III cation is located in an RhC₅N₂Cl eight‐coordinated environment. In the crystal, 1‐hydroxypyrrolidine‐2,5‐dione (NHS) solvent molecules form strong hydrogen bonds with the Cl⁻ counter‐anions in the lattice and weak hydrogen bonds with the pentamethylcyclopentadienyl (Cp*) ligands. Hydrogen bonding between the Cp* ligands, the NHS solvent molecules and the Cl⁻ counter‐anions form links in a V‐shaped chain of Rh^III complex cations along the c axis. Weak hydrogen bonds between the dimethyl 2,2′‐bipyridine‐4,4′‐dicarboxylate ligands and the Cl⁻ counter‐anions connect the components into a supramolecular three‐dimensional network. The synthetic route to the dimethyl 2,2′‐bipyridine‐4,4′‐dicarboxylate‐containing rhodium complex from the [bis(2,5‐dioxopyrrolidin‐1‐yl) 2,2′‐bipyridine‐4,4′‐dicarboxylate]rhodium(III) precursor may be applied to link Rh catalysts to the surface of electrodes.     

μ‐2,2′,6,6′‐Tetramethyl‐4,4′‐bipyridine‐κ2N1:N1′‐bis[(diethylenetriamine‐κ3N,N′,N′′)palladium(II)] tetranitrate

The title compound, [Pd₂(C₄H₁₃N₃)₂(C₁₄H₁₆N₂)](NO₃)₄, comprises discrete tetracationic dumbbell‐type dinuclear complex molecules and noncoordinating nitrate anions. Two Pd(dien)²⁺ moieties (dien is diethylenetriamine) are joined by the rigid linear exo‐bidentate bridging 2,2′,6,6′‐tetramethyl‐4,4′‐bipyridine ligand to form the dinuclear complex, which lies across a centre of inversion in the space group P2₁/n, so that the rings in the 2,2′,6,6′‐tetramethyl‐4,4′‐bipyridine bridging ligand are parallel. In the crystal, the primary and secondary amino groups of the dien ligand act as hydrogen‐bond donors towards the nitrate anions to form a three‐dimensional hydrogen‐bond network.     

catena‐Poly[[silver(I)‐μ‐[(E)‐1,2‐bis(2‐pyridyl)ethylene‐N:N′]] nitrate]

In the title complex, {[Ag(C₁₂H₁₀N₂)]NO₃}_n, the Ag atom, which is in a linear AgN₂ geometry, is surrounded by two trans‐related N atoms of two bpe ligands [Ag—N = 2.173 (3) and 2.176 (3) Å; bpe is trans‐1,2‐bis(2‐pyridyl)­ethyl­ene]. The bpe ligands bridge neighbouring Ag atoms to form zigzag polymeric chains in the lattice. These adjacent one‐dimensional zigzag chains are extended into a three‐dimensional supramolecular array by strong interchain π?π interactions between the pyridyl rings of adjacent chains.     

catena‐Poly[[bis(nitrato‐κ2O,O′)copper(II)]‐μ‐propane‐1,3‐diylbis(diphenylphosphine oxide)‐κ2O:O′]

The structure of the title complex, [Cu(NO₃)₂(C₂₇H₂₆O₂P₂)]_n, consists of polymeric chains formed by propane‐1,3‐diylbis(diphenylphosphine oxide) ligands bridging between metal centres. The Cu atom lies on a twofold rotation axis and a further symmetry centre bisects the bridging bisphosphine dioxide ligand. The CuO₆ coordination geometry is a distorted octahedron, with the bidentate chelating nitrate groups adopting a cis configuration.     

catena‐Poly­[[di‐μ‐benzoato‐κ4O:O′‐disilver(I)]‐μ‐N,N′‐bis(2‐fluoro­benzyl­idene)­butane‐1,4‐di­amine‐κ2N:N′]

The title complex, [Ag₂(C₇H₅O₂)₂(C₁₈H₁₈F₂N₂)]_n, is a dinuclear silver(I) compound with one inversion centre between pairs of Ag atoms and another at the mid‐point of the central C—C bond in the butane‐1,4‐diamine moiety. Each of the smallest repeat units consists of two silver(I) cations, two benzoate anions and one N,N′‐bis(2‐fluorobenzyl­idene)­butane‐1,4‐di­amine Schiff base ligand. Each Ag^I ion is three‐coordinated in a trigonal configuration by two O atoms from two benzoate anions and one N atom from a Schiff base ligand. The di‐μ‐benzoato‐disilver(I) moieties are linked by the bridging Schiff base ligand, giving zigzag polymeric chains with an [–Ag⋯Ag—N—C—C—C—C—N–]_n backbone running along the b axis.     

catena‐Poly[[(1,10‐phenanthroline‐κ2N,N′)manganese(II)]‐di‐μ‐salicylato‐κ4O:O′]

In the title polymeric complex, [Mn(C₇H₅O₃)₂(C₁₂H₈N₂)]_n, the Mn^II atom is located on a twofold axis and displays a distorted octa­hedral coordination geometry, formed by four salicylate anions and one 1,10‐phenanthroline (phen) mol­ecule. The salicylate anions doubly bridge the Mn^II atoms to form one‐dimensional polymeric chains. A comparison of Mn—O bond distances with the corresponding Mn—O—C angles suggests a significant electrostatic content in the Mn—O bonds. A face‐to‐face distance of 3.352 (7) Å between neighbouring parallel phen planes indicates π–π stacking inter­actions between polymeric chains.     

A novel three‐dimensional heterometallic coordination polymer: poly[[diaquadi‐μ3‐chlorido‐μ2‐chlorido‐tri‐μ3‐nicotinato‐tricopper(I)gadolinium(III)] hemihydrate]

In the title polymeric heterometallic compound, {[Cu₃Gd(C₆H₄NO₂)₃Cl₃(H₂O)₂]·0.5H₂O}_n, comprising copper(I) and gadolinium(III) cations bridged by nicotinate (nic) ligands and chloride anions, the Gd^III centers display a bicapped trigonal prismatic geometry, defined by six carboxylate O atoms and two water molecules. For copper(I), one Cu center is three‐coordinated by three chloride ions and displays a trigonal–planar geometry; the other two Cu centers are four‐coordinated and display a very distorted tetrahedral geometry. The chloride anions act in μ₂‐ and μ₃‐bridging modes, linking the Cu^I ions into an infinite chain. The nic ligand exhibits a tridentate coordination mode, with the carboxylate O atoms linking to two Gd^III ions and the N atom linking to one Cu^I ion. Thus, a novel three‐dimensional heterometallic coordination polymer is constructed from Gd–carboxylate subunits and Cu—Cl chains. In addition, intra‐ and intermolecular O—H...O and O—H...Cl hydrogen bonds are also observed within the three‐dimensional structure. Topologically, the framework represents an unusual 3,6‐connected (4.8²)₃(4¹⁰.6⁵) net.     

Aluminium Complexes Bearing Pyrrolide Ligand as Efficient Catalysts for Ring‐Opening Polymerization of ε‐Caprolactone

Three aluminium complexes supported by a tetradentate pyrrolide ligand H₂L [H₂L = N,N′‐(2,2‐dimethylpropane‐1,3‐diyl)bis(1‐(1H‐pyrrol‐2‐yl)methanimine)], namely, Al(L)Me ( 1 ), Al(L)Cl ( 2 ), and Al(L)(OiPr) ( 3 ), were synthesized. The structures of 1 and 2 were established by X‐ray single crystal diffraction analysis, and the structure of 3 was characterized by NMR spectroscopy and element analysis. All complexes, containing different chemical bond forms (Al–C, Al–Cl, and Al–O), are good initiators for the ring‐opening polymerization (ROP) of ε‐caprolactone. The obtained polymers have high molecular weights (MWs) and relatively narrow molecular weight distributions (PDIs). Complexes 1 and 3 show dramatically high activities for the ROP of ε‐caprolactone. For complex 1 , when the monomer/initiator (M/I) ratio is 6400:1, a 40 % yield of the product could be obtained at 100 °C. The activity of 3 is higher than that of 1 , and 39 % yield of the polymers could be afforded at 70 °C, as the M/I value reaches 12800:1. The good activities of these complexes reveal their potential applications in industry.     

catena‐Poly­[[silver(I)‐μ‐hexane‐1,6‐di­amine‐κ2N:N′] cinnamate dihydrate]

The title compound, {[Ag(C₆H₁₆N₂)](C₉H₇O₂)·2H₂O}_n, has been synthesized and characterized by elemental analysis and single‐crystal X‐ray diffraction. The Ag atom is coordinated in a linear configuration by two N atoms from two hexane‐1,6‐­diamine ligands, giving a zigzag polymeric chain with an [–Ag—N—C—C—C—C—C—C—N–]_n backbone running parallel to the c axis. In the crystal packing, adjacent chains interact with the anions via the lattice water mol­ecules, thus forming layers parallel to the bc plane.     

Poly[μ2‐chloro‐μ2‐1,4‐oxathiane‐κ2S:S‐copper(I)]

The title complex, [CuCl(C₄H₈OS)]_n, contains infinite spiral (CuS)_n chains linked by bridging Cl atoms into layers. The Cl atoms do not form polymeric fragments with Cu^I, but combine into isolated centrosymmetric Cu₂Cl₂ units. The compound is non‐isomorphous with the Br‐containing analogue, which contains Cu₈S₈ rings linked by Br atoms into chains. The O atom of the 1,4‐oxathiane mol­ecule does not realize its coordination abilities in the known copper(I)–halide complexes, while in copper(II)–halide complexes, oxathiane is coordinated via the S and O atoms. This falls into a pattern of the preferred inter­actions, viz. weak acid (Cu^I atom) with weak base (S atom) and harder acid (Cu^II atom) with harder base (O atom).