Silver(I) sulfate coordination polymers with 4,4′‐bipyridazine and pyridazino[4,5‐d]pyridazine

Poly[[μ₄‐4,4′‐bipyridazine‐μ₅‐sulfato‐disilver(I)] monohydrate], {[Ag₂(SO₄)(C₈H₆N₄)]·H₂O}_n, (I), and poly[[aqua‐μ₄‐pyridazino[4,5‐d]pyridazine‐μ₃‐sulfato‐disilver(I)] monohydrate], {[Ag₂(SO₄)(C₆H₄N₄)(H₂O)]·H₂O}_n, (II), possess three‐ and two‐dimensional polymeric structures, respectively, supported by N‐tetradentate coordination of the organic ligands [Ag—N = 2.208 (3)–2.384 (3) Å] and O‐pentadentate coordination of the sulfate anions [Ag—O = 2.284 (3)–2.700 (2) Å]. Compound (I) is the first structurally examined complex of the new ligand 4,4′‐bipyridazine; it is based upon unprecedented centrosymmetric silver–pyridazine tetramers with tetrahedral AgN₂O₂ and trigonal–bipyramidal AgN₂O₃ coordination of two independent Ag^I ions. Compound (II) adopts a typical dimeric silver–pyridazine motif incorporating two kinds of square‐pyramidal AgN₂O₃ Ag^I ions. The structure exhibits short anion–π interactions involving noncoordinated sulfate O atoms [O...π = 3.041 (3) Å].     

Syntheses,Structures and Spectroscopic Studies of Silver(I) Coordination Polymers Bridged by Flexible Bidentate Ligands

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) ų, 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.     

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.     

Influence of organic carboxylic acids on self-assembly of silver(I) complexes containing 1,2-bis(4-pyridyl)ethane ligands

Four silver(I) complexes, namely [Ag₂(bpe)₂](bdc)·8H₂O (1), [Ag₂(bpe)₂(da)]·4H₂O (2), [Ag₄(bpe)₃(bptc)]·9H₂O (3), and Ag(bpe)₂(bpdc)₂ (4), have been successfully synthesized by the reactions between AgNO₃, 1,2-bis(4-pyridyl)ethane (bpe) and different carboxylic acids, including 1,3-benzenedicarboxylic acid (H₂bdc), diphenic acid (H₂da), 3,3′,4,4′-biphenyltetracarboxylic acid (H₄bptc), and 2,2′-bipyridine-3,3′-dicarboxylic acid (H₂bpdc). All four compounds were characterized by elemental analysis, IR spectra, and single-crystal X-ray diffraction. In (1), the Ag(I) atoms, in linear geometry, are joined into 1-D infinite cationic bpe-silver chains, and discrete bdc²⁻ anions compensate the charge of the crystal structure. In (2), the Ag(I) atoms, adopting tetrahedral and trigonal geometries, are linked by bpe and da²⁻ ligands into neutral double chains. In (3), the Ag(I) atoms, in T-shaped and linear environments, are coordinated by bpe and multidentate bptc⁴⁻ ligands to construct a 2-D network. And in (4), the Ag(I) atoms, with trigonal and T-shaped coordination geometries, are coordinated by bpe and bpdc²⁻ ligands to build up a 3-D framework. The different anions play different and important roles in directing the final crystal structures.     

Syntheses and Structural Characterization of Four New Silver(I) Complexes with the N,N′(O)‐bidentate Bridging Ligands

Four new bridged silver(I) complexes, namely [Ag₂(μ₂‐teda)(μ₂‐fbc)₂] ( 1 ), [Ag₂(μ₂‐1,6‐dah)₂](bpdc) · 4H₂O ( 2 ), [Ag₂(μ₂‐2‐ap)(2‐ap)(bnb)] · 0.34H₂O ( 3 ), [Ag₂(μ₂‐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) [Ag₂(μ₂‐2‐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) [Ag₂(μ₂‐pyc)₂(2‐apy)₂] moiety and half lattice water molecule, further generating a tetranuclear silver(I) {[Ag₂(μ₂‐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.     

Crystal Structures of [Mn2(H2O)4(phen)2(C4H4O4)2] · 2 H2O and [Mn(phen)2(H2O)2][Mn(phen)2(C4H4O4)](C4H4O4) · 7 H2O

Reactions of 1,10‐phenanthroline monohydrate, Na₂C₄H₄O₄ · 6 H₂O and MnSO₄ · H₂O in CH₃OH/H₂O yielded a mixture of [Mn₂(H₂O)₄(phen)₂(C₄H₄O₄)₂] · 2 H₂O ( 1 ) and [Mn(phen)₂(H₂O)₂][Mn(phen)₂(C₄H₄O₄)](C₄H₄O₄) · 7 H₂O ( 2 ). The crystal structure of 1 (P1 (no. 2), a = 8.257(1) Å, b = 8.395(1) Å, c = 12.879(2) Å, α = 95.33(1)°, β = 104.56(1)°, γ = 106.76(1)°, V = 814.1(2) ų, Z = 1) consists of the dinuclear [Mn₂(H₂O)₄(phen)₂(C₄H₄O₄)₂] molecules and hydrogen bonded H₂O molecules. The centrosymmetric dinuclear molecules, in which the Mn atoms are octahedrally coordinated by two N atoms of one phen ligand and four O atoms from two H₂O molecules and two bis‐monodentate succinato ligands, are assembled via π‐π stacking interactions into 2 D supramolecular layers parallel to (101) (d(Mn–O) = 2.123–2.265 Å, d(Mn–N) = 2.307 Å). The crystal structure of 2 (P1 (no. 2), a = 14.289(2) Å, b = 15.182(2) Å, c = 15.913(2) Å, α = 67.108(7)°, β = 87.27(1)°, γ = 68.216(8)°, V = 2934.2(7) ų, Z = 2) is composed of the [Mn(phen)₂(H₂O)₂]²⁺ cations, [Mn(phen)₂(C₄H₄O₄)] complex molecules, (C₄H₄O₄)^2– anions, and H₂O molecules. The (C₄H₄O₄)^2– anions and H₂O molecules form 3 D hydrogen bonded network and the cations and complex molecules in the tunnels along [001] and [011], respectively, are assembled via the π‐π stacking interactions into 1 D supramolecular chains. The Mn atoms are octahedrally coordinated by four N atoms of two bidentate chelating phen ligands and two water O atoms or two carboxyl O atoms (d(Mn–O) = 2.088–2.129 Å, d(Mn–N) = 2.277–2.355 Å). Interestingly, the succinato ligands in the complex molecules assume gauche conformation bidentately to chelate the Mn atoms into seven‐membered rings.     

Syntheses and Crystal Structures of Three Polymeric Silver(I) Terephthalate Complexes with Organic N‐Donor Ligands: [Ag(pren)]2(tp)·2H2O, [Ag(en)][Ag(μ2‐tp)]·H2O,and [Ag2(μ4‐tp)(apy)2]

Three polymeric silver(I) complexes with terephthalate anions as counterions or ligands, [Ag(pren)]₂(tp)·2H₂O ( 1 ), [Ag(en)][Ag(μ₂‐tp)]·H₂O ( 2 ), and [Ag₂(μ₄‐tp)(apy)₂] ( 3 ) (where pren = 1, 2‐propylenediamine, tp =terephthalate dianion, en = ethylenediamine, and apy = 2‐aminopyridine) were synthesized and characterized by X‐ray single crystal analysis and infrared spectroscopy. 1 crystallizes in the monoclinic space group P2₁1/c with a = 11.3221(5), b = 7.1522(3), c = 14.8128(5)Å, V = 1015.77(7)ų, β = 122.132(2), and Z = 2. 2 crystallizes in the orthorhombic space group Pnma with a = 9.6144(6), b = 11.3465(7), c = 11.4810(7)Å, V = 1252.5(1)ų, and Z = 4. 3 crystallizes in the monoclinic space group P2₁/n with a = 8.2003(5), b = 5.8869(4), c = 18.3769(11)Å, β = 92.593(1), V = 886.2(1)ų, and Z = 4. Terephthalate dianions are not coordinated to the metal atoms in 1 , but act as a μ₂‐bridging ligand in 2 and as a μ₄‐bridging ligand in 3 .     

Synthesis, crystal structure, and luminescent properties of a silver(I) perrhenate complex with phenazine

The silver complex with phenazine [Ag(Phz)₂(H₂O)]ReO₄ (Phz is C₁₂H₈N₂) has been synthesized, and its crystal structure has been determined. The crystals are triclinic: space group $P\bar 1$ , a = 9.587(1) Å, b = 10.875(1) Å, c = 11.668(1) Å, α = 104.98(1)°, β = 103.87(1)°, γ = 92.94(1)°, V = 1132.6(2) ų, Z = 2, ρ_calc = 2.160 g/cm³. The structure is composed of the [Ag(Phz)₂(H₂O)]⁺ silver cationic complexes and ReO ₄ ^? anions. The Ag⁺ ion is coordinated by two nitrogen atoms of independent phenazine molecules and the water oxygen atoms and has a T-shaped coordination (Ag-N_av 2.223 Å, Ag-O_w 2.498(8) Å). Phenazine, being an electron-donor ligand, forms columns due to π-π stacking interaction between the aromatic groups. The water molecules form hydrogen bonds with the oxygen atoms of water molecules of neighboring complexes and with oxygen atoms of the ReO ₄ ^? anions.     

Silver(I) Complexes of Schiff Bases Derived from Thiophene-2,5-dicarboxaldehyde and Furan-2,5-dicarboxaldehyde

The reactions of Schiff bases, derived by the condensation of thiophene-2,5-dicarbaldehyde and furan-2,5-dicarbaldehyde with 2-thienylmethylamine or 2-furanmethylamine, with silver nitrate have been studied in refluxing anhydrous methanol under nitrogen atmosphere. Complexes thus formed have been isolated and characterized by elemental analysis, electrical conductance, cyclic voltammetry, and ¹H NMR, ¹³C NMR, IR, LTV-Vis, and mass spectroscopic studies. The experimental results reveal that the complexes are primarily ionic in nature, consisting of (L)₃Ag₂ dication and Ag(NO₃)₃ negatively charged dianions. The molecular structure of one of the complexes, [((C₄H₃O)CH₂N? CH(C₄H₂S)CH? NCH₂(C₄H₃O))₃Ag₂] [Ag(NO₃)₃] has been studied in the solid state. The complex is crystallized in the triclinic space group $ {\rm P}\bar 1 $ with a = 12.889(7) Å, b = 14.884(5) Å, c = 15.084(6) Å, α = 92.18(4)°, β = 79.78(4)°, γ = 110.92(4)°. The structure is disordered. Each Ag in dication is tri-coordinated by three azomethine N atoms from three ligands, and each ligand employs two azomethine N atoms to coordinate to two Ag ions such that the geometry around the Ag ?Ag axis conforms to a propeller-shape. The two Ag ions are between the two N₃ planes with Ag ? Ag distance ca. 4.8.1 Å. There is no bonding between any Ag ion and any thiophene of the three ligands. However, two Ag ions and three thiophene S atoms form a trigonal bipyramidal geometry.     

Complexes of AgI with cationic ligands: bis[(pyridylmethyl)ammonio]silver(I) salts

Bis­[(2-pyridyl­methyl)­ammonio]silver(I) trinitrate, [Ag(C₆H₉N₂)₂](NO₃)₃, (I), and bis{bis­[(4-pyridyl­methyl)­ammonio]silver(I)} hexakis­(perchlorate) dihydrate, [Ag(C₆H₉N₂)₂]₂(ClO₄)₆·2H₂O, (II), are rare examples of complexes with cationic ligands. In (I), the Ag⁺ cation has a T-shaped [2+1] coordination involving the pyridine N atoms and a nitrate O atom, while in (II) there are three independent two-coordinate Ag complex cations (two with the Ag atoms on independent inversion centres) and disordered ClO₄⁻ ions. The crystal structures reveal the role of hydrogen bonding in stabilizing these complexes.     

Polysulfonylamine. XLI. Ein Silber(I)-Hydrat ungewöhnlicher Zusammensetzung: Röntgenstrukturanalytische und thermochemische Charakterisierung von Tetrakis(dimesylamido)aquatetrasilber(I) [Ag4(N(SO2CH3)2}4(H2O)]

Polysulfonyl Amines. XLI. A Silver(I) Hydrate with an Unusual Composition: Characterization of Tetrakis(dimesylamido)aquatetrasilver(I) [Ag₄(N)SO₂CH₃)₂}₄(H₂O)] by X-Ray Diffraction and Thermal Analysis The title compound is obtained by crystallizing AgN(SO₂CH₃)₂ from water at room temperature. Crystallographic data (at ?95°C): Triclinic space group P1 , a = 864.6(4), b = 1 211.2(5), c = 1 399.1(5) pm, α = 90.97(3), β = 90.90(3), γ = 98.25(4)°, V = 1.4496 nm³, Z = 2, D_x = 2.608 Mg m^?3. The four independent silver atoms and the water molecule form zigzag chains Ag(1)-Ag(2)-(μ-H₂O)-Ag(3) …? Ag(4) …? Ag(1′) with distances Ag(1)-Ag(2) 309.7, Ag(2)-O(w) 241.8, O(w)-Ag(3) 241.4, Ag(3) …? Ag(4) 342.9, Ag(4) …? Ag(1′) 361.4 pm. The catenated silver atoms are further connected by the dimesylamide anions acting as tridentate bridging (α-O, N, ω-O)-ligands. The resulting strands are interconnected into layers through one O(S)-Ag′ contact (247 pm) and one hydrogen bond O(w)-H(l) …? O′(S) per repeating unit. Between the layers, a weak O(S) …? Ag″ interaction (271 ptn) and a hydrogen bond O(w)-H(2) …? O(S) per repeating unit are observed. The silver atoms Ag(l) to Ag(4) display the coordination numbers 5 [NO,Ag(2), distorted trigonal bipyramid], 5[NO₂,O(w)Ag(I), distorted trigonal bipyramid], 5[O₄,O(w), trigonal bipyramid], and 2 + 1 (N₂, li-near; plus a secondary Ag …? 0 contact). The dehydration of the title compound and a solid-solid phase transformation in anhydrous AgN(SO₂CH₃)₂, were quantitatively investigated by thermoconductometry and time- and temperature-resolved X-ray diffractometry (TXRD).     

Homo- und heterodinukleare α-Pyridonat-verbrückte Platin- und Palladium-komplexe mit Bis(N-methylimidazol-2-yl)keton (BMIK). Kristallstrukturen von [(BMIK)Pt(α-Pyridonat)2Pt(BMIK)](NO3)2 · 4H2O, [(BMIK)Pd(α-Pyridonat)2Pd(BMIK)](NO3)2 · 4H2O und [(BMIK)Pd(α-Pyridonat)2Pt/Pd(BMIK)](NO3)2 · 4H2O

Homo- and Heterodinuclear α-Pyridonate-bridged Platinum and Palladium Complexes with Bis(N-methylimidazol-2-yl)ketone (BMIK). Crystal Structures of [(BMIK)Pt(α-pyridonate)₂Pt(BMIK)](NO₃)₂ · 4H₂O, [(BMIK)Pd(α-pyridonate)₂Pd(BMIK)](NO₃)₂ · 4H₂O, and [(BMIK)Pd(α-pyridonate)₂Pt/Pd(BMIK)](NO₃)₂ · 4H₂O The isotypic dinuclear complexes [(BMIK)Pt(α-pyridonate)₂Pt(BMIK)](NO₃)₂ · 4H₂O ( 1 ) (P1 ; a = 12.197(5) Å, b = 12.505(5) Å, c = 12.866(5) Å, α = 88.17(3)°, β = 73.55(3)°, γ = 69.84(3)°; Z = 2) and [(BMIK)Pd(α-pyridonate)₂Pd(BMIK)](NO₃)₂ · 4H₂O ( 2 ) (a = 12.408(3) Å, b = 12.660(3) Å, c = 12.913(3) Å, α = 89.55(3)°, β = 74.59(2)°, γ = 68.68(2)°) were prepared by reaction of [Pt(BMIK)(H₂O)₂](NO₃)₂ or [Pd(BMIK)(H₂O)₂](NO₃)₂ with α-pyridone in aqueous solutions at 40°C and were isolated as red air-stable crystals (BMIK = bis(N-methylimidazol-2-yl)ketone). For the synthesis of mixed crystals of 2 with the heterometal complex [(BMIK)Pd(α-pyridonate)₂Pt(BMIK)](NO₃)₂ · 4H₂O ( 3 ) (a = 12.430(4) Å, b = 12.648(3) Å, c = 12.907(4) Å, α = 89.64(2)°, β = 74.57(2)°, γ = 68.65(2)°) α-pyridone was reacted with [Pd(BMIK)(H₂O)₂](NO₃)₂ in a molar ratio of 2 : 1 followed by addition of [Pt(BMIK)(H₂O)₂](NO₃)₂. The dinuclear cations consist of two M(BMIK) moieties (M = Pt, Pd) bridged by the N- and O-atoms of α-pyridonate, forcing the heterocyclic ring into head-head-orientation. Within the dinuclear cation, the two metal atoms are between 2.840 Å and 2.860 Å apart. The intermolecular distances are between 4.762 Å and 4.837 Å. The coordination geometry of both metal atoms is square-planar with the metal atoms being diplaced slightly from their respective coordination planes toward each other. ¹H and ¹⁹⁵Pt NMR spectra are reported for the complexes.     

Polysulfonylamine. XLII. Ein Aquasilber(I)-Komplex mit einem Ag(m̈-H2O)2Ag-Strukturmotiv: Röntgenstrukturanalytische und thermoanalytische Charakterisierung von Aqua(1,1,3,3-tetraoxo-1,3,2-benzodithiazolido)silber(I)

Polysulfonyl Amines. XLII. An Aquasilver(I) Complex with an Ag(m?-H₂O)₂Ag Structural Unit: Characterization of Aqua(1,1,3,3-tetraoxo-1,3,2-benzodithiazolido)silver(I) by X-Ray Diffractometry and Thermal Analysis The title compound C₆H₄(SO₂)₂NAg · H₂O, where C₆H₄(SO₂)₂N^º is the anion of 1,2-benzenedisulfonimide, crystallizes in the monoclinic space group C2/m with (at ?95°C) a = 1 129,7(3), b = 1 196.1(3), c = 810.7(2) pm, β = 124.25(2)°, V = 0.9055 nm³, Z = 4, D_x = 2.524 Mg m^?3. The crystal packing consists of [Ag(m?-H₂O)₂Ag{m?-C₆H₄(SO₂)₂N}₂]_n bands with crystallographic mirror symmetry, associated into layers by H-bonds with O(W)—O(S) 289.7 pm. The Ag(m?-H₂O)₂Ag moiety forms a planar four-membered ring with Ag? O(W)? Ag 97.3°, O(W)? Ag? O(W) 82.7° and Ag°Ag 372.1 pm. In the Ag{C₆H₄(SO₂)₂N}₂Ag′ unit, the anions act as tridentate (N, 1-O, 3-O)-ligands: One is N-bonded to Ag and O,O-chelated to Ag′, the other N-bonded to Ag′ and O,O-chelated to Ag. The silver atoms are (O₄N)-pentacoordinate, with nitrogen in the apical position of a distorted square pyramid [Ag? N 223.6, Ag? O(W) 247.8, Ag? O(S) 259.4 pm]. The thermochemical behaviour of the hydrate was investigated by thermal analysis and calorimetry. Water is only released at temperatures above 220°C. The dehydration enthalpy at 298 K is + 13.9 kJ mol^?1.     

Aqua(dipicolinato‐κ3O2,N,O6)(1,10‐phenanthroline‐κ2N,N′)manganese(II) monohydrate

In the title compound [systematic name: aqua(1,10‐phenanthroline‐κ²N,N′)(pyridine‐2,6‐di­carboxyl­ato‐κ³O²,N,O⁶)manganese(II) monohydrate, [Mn(C₇H₃NO₄)(C₁₂H₈N₂)(H₂O)]·H₂O, the manganese(II) centre is surrounded by one bidentate phenanthroline ligand [Mn—N = 2.248 (3) and 2.278 (3) Å], one tridentate dipicolinate ligand [Mn—N = 2.179 (3) Å, and Mn—O = 2.237 (2) and 2.266 (2) Å] and one water mol­ecule [Mn—O = 2.117 (3) Å], and it exhibits a strongly distorted octahedral geometry, with trans angles ranging from 144.12 (9) to 158.88 (11)°. Extensive intermolecular hydrogen‐bonding interactions involving coordinated and uncoordinated water mol­ecules and the carboxyl O atoms of the dipicolinate ligand, as well as a stacking interaction involving the phenanthroline rings, are observed in the crystal structure.     

Bis(4‐aminopyridine)silver(I) nitrate and tris(2,6‐diaminopyridine)silver(I) nitrate

The bis(4‐aminopyridine)silver(I) cation in [Ag(C₅H₆N₂)₂]NO₃ has the Ag atom on a twofold axis and displays an N—Ag—N angle of 174.43 (15)° and an Ag—N distance of 2.122 (3) Å. The two ligands are planar and the angle between the two ligand planes is 79.45 (9)°. The pyridine rings are stacked in piles with an interplanar distance of 3.614 (5) Å, a distance that strongly suggests that pyridine π–π interactions have an appreciable importance with respect to the non‐bonded crystal organization. The tris(2,6‐diaminopyridine)­silver(I) cation in [Ag(C₅H₇N₃)₃]NO₃ has Ag—N distances of 2.243 (2), 2.2613 (17) and 2.4278 (18) Å, and N—Ag—N angles of 114.33 (7), 134.91 (7) and 114.33 (7)°. The Ag⁺ ion is situated 0.1531 (2) Å from the plane defined by the three pyridine N atoms.     

Synthesis,Spectrothermal Behaviour and Molecular Structure of Aquaorotatotriethanolaminenickel(II) Monohydrate

The aquaorotatotriethanolaminenickel(II) monohydrate, [Ni(HOr)(H₂O)(tea)]·H₂O ( 1 ), was synthesized and characterized by means of elementel analysis, IR and UV‐Vis, spectroscopy, magnetic susceptibility, thermal analysis and X‐ray diffraction techniques. The nickel ion in [Ni(C₅H₂N₂O₄)(H₂O)(N(C₂H₄OH)₃)] is chelated to the deprotonated N3 pyrimidine atom and to the carboxylate oxygen atom of the bidentate orotate dianion, and to the one nitrogen and two oxygen atoms of the tridentate triethanolamine molecule and its octahedral geometry is completed by an aqua ligand. It crystallizes in the monoclinic system, space group P2₁/c with lattice parameters a = 7.1528(5) Å, b = 19.4903(14) Å, c = 11.8085(8) Å, β = 106.237(5)°, V = 1580.55(19) ų, Z = 4. An extensive three dimensional network of O_w‐H…O, N‐H…O and O‐H…O hydrogen bonds, π‐π and π‐ring interactions are responsible for crystal stabilization. The decomposition reaction take places in the temperature range 20‐1000 °C in the static air atmosphere. Thermal decomposition of 1 proceeds in three stages.     

Synthesis,Characterization and Biological Evaluation of Two Silver(I) trans‐Cinnamate Complexes as Urease Inhibitors

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‐η¹:η¹ 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.     

Supramolecular Assemblies of Mononuclear and Polymeric Nickel(II) Glutarato Complexes via π‐π Stacking Interactions and Hydrogen Bonds: [Ni(H2O)3(phen)(C5H6O4)] · H2O and [Ni(H2O)2(phen)(C5H6O4)]

Syntheses of the sky blue complex compounds [Ni(H₂O)₃(phen)(C₅H₆O₄)] · H₂O ( 1 ) and [Ni(H₂O)₂(phen)(C₅H₆O₄)] ( 2 ) were carried out by the reactions of 1,10‐phenanthroline monohydrate, glutaric acid, NiSO₄ · 6 H₂O and Na₂CO₃ in CH₃OH/H₂O at pH = 6.9 and 7.5, respectively. The crystal structure of 1 (P 1 (no. 2), a = 14.289 Å, b = 15.182 Å, c = 15.913 Å, α = 67.108°, β = 87.27°, γ = 68.216°, V = 2934.2 ų, Z = 2) consists of hydrogen bonded [Ni(H₂O)₃‐ (phen)(C₅H₆O₄)]₂ dimers and H₂O molecules. The Ni atoms are octahedrally coordinated by two N atoms of one phen ligand, three water O atoms and one carboxyl O atom from one monodentate glutarato ligand (d(Ni–N) = 2.086, 2.090 Å; d(Ni–O) = 2.064–2.079 Å). Through the π‐π stacking interactions and intermolecular hydrogen bonds, the dimers are assembled to form 2 D layers parallel to (0 1 1). The crystal structure of 2 (P2₁/n (no. 14), a = 7.574 Å, b = 11.938 Å, c = 18.817 Å, β = 98.48°, V = 1682.8 ų, Z = 4) contains [Ni(H₂O)₂(phen)(C₅H₆O₄)_2/2] supramolecular chains extending along [010]. The Ni atoms are octahedrally coordinated by two N atoms of one phen ligand, two water O atoms and two carboxyl O atoms from different bis‐monodentate glutarato ligands with d(Ni–N) = 2.082, 2.105 Å and d(Ni–O) = 2.059–2.087 Å. The supramolecular chains are assembled into a 3 D network by π‐π stacking interactions and interchain hydrogen bonds. A TG/DTA of 2 shows two endothermic effects at 132 °C and 390 °C corresponding to the complete dehydration and the lost of phen.     

Two Heteroleptic Zinc(II) Complexes: [Zn(phen)(C9H15O6)2] and [Zn2(phen)2(H2O)2(C10H16O4)2] · 3H2O

Reactions of a freshly prepared Zn(OH)_2‐2x(CO₃)x · yH₂O precipitate, phenanthroline with azelaic and sebacic acid in CH₃OH/H₂O afforded [Zn(phen)(C₉H₁₅O₄)₂] ( 1 ) and [Zn₂(phen)₂(H₂O)₂(C₁₀H₁₆O₄)₂] · 3H₂O ( 2 ), respectively. They were structurally characterized by X‐ray diffraction methods. Compound 1 consists of complex molecules [Zn(phen)(C₉H₁₅O₄)₂] in which the Zn atoms are tetrahedrally coordinated by two N atoms of one phen ligand and two O atoms of different monodentate hydrogen azelaato groups. Intermolecular C(alkyl)‐H···π interactions and the intermolecular C(aryl)‐H···O and O‐H···O hydrogen bonds are responsible for the supramolecular assembly of the [Zn(phen)(C₉H₁₅O₄)₂] complexes. Compound 2 is built up from crystal H₂O molecules and the centrosymmetric binuclear [Zn₂(phen)₂(H₂O)₂(C₁₀H₁₆O₄)₂] complex, in which two [Zn(phen)(H₂O)]²⁺ moieties are bridged by two sebacato ligands. Through the intermolecular C(alkyl)‐H···O hydrogen bonds and π‐π stacking interactions, the binuclear complex molecules are assembled into layers, between which the lattice H₂O molecules are sandwiched. Crystal data: ( 1 ) C2/c (no. 15), a = 13.887(2), b = 9.790(2), c = 22.887(3)Å, β = 107.05(1)°, U = 2974.8(8)ų, Z = 4; ( 2 ) P1¯ (no. 2), a = 8.414(1), b = 10.679(1), c = 14.076(2)Å, α = 106.52(1)°, β = 91.56(1)°, γ = 99.09(1)°, U = 1193.9(2)ų, Z = 1.     

Synthesis and crystal structure of the coordination polymer of silver with 4,4′-bipyridylethylene [Ag(Bpe)](NO3)·3H2O

The compound [Ag(Bpe)](NO₃)·3H₂O (Bpe = 4,4′-bipyridylethylene, C₁₂H₁₀N₂) is prepared and its crystal structure is determined. The crystals are triclinic: a = 9.073(2) Å, b = 10.074(2) Å, c = 10.391(2) Å, α = 61.18(3)°, β = 72.11(3)°, γ = 68.62(3)°, space group P $\bar 1$ , V = 764.7(3) ų, ρ(calcd) = 1.764 g/cm³, Z = 2. The structure is composed of polymeric cationic chains, [Ag(Bpe)] _∞ ⁺ , NO ₃ ^? counterions, and water molecules. The Ag⁺ ions are bound to the two N atoms of two crystallographically nonequivalent Bpe ligands and form a nearly linear coordination (Ag(1)-N(1), 2.129 Å; Ag(1)-N(2), 2.120(4) Å; N(1)Ag(1)N(2), 169.9(2)°).