Synthesis and Structure of Di-μ-oxo-bistripyrazolylborato Dioxo Vanadium (V) Complex with Lattice of Diacetonitrile

Abstract A novel oxovanadium complex was obtained by the reaction of VOSO₄ · 3H₂O with tripyrazolylborate sodium in MeOH. The complex (1) was characterized by element analysis, IR spectroscopy, ¹HNMR and its crystal for X-ray diffraction recrystallized from saturated CH₃CN solution. The compound crystallizes in the monoclinic, space group Pbca, with cell dimensions of a = 15.531(2) ?; b = 18.007(2) ?; c = 10.725(2) ?; V = 2,999.4(8) ?³ and D _calc = 1.533 g/cm³ for Z = 4. The structure was solved by direct methods and refined to an R-value of 0.0401. Structure analysis show that it is a di-μ-oxo-bistripyrazolylborato dioxo vanadium (V) complex with lattice of diacetonitrile. In addition, the electronic structure and the bonding characters of the complex were analyzed with ab initio calculations. Index Abstract Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.     

Synthesis and Crystal Structure Analysis of Thiourea-Pendant Pyridines

Abstract  The crystal structures of pyridine containing thiourea moieties as substituents, (1) and (2), have been determined. The ortho-substituted pyridine (1) crystallized in monoclinic space group P2₁/c with a = 16.091(3) ?, b = 11.368(2) ?, c = 7.4364(14) ?, β = 100.489(4)o, V = 1337.5(4) ?³, z = 4. In this structure an intramolecular N–H···N hydrogen bond forms a pseudo-seven-membered ring. The meta-substituted pyridine (2) crystallized in monoclinic space group P2₁/c with a = 14.5408(15) ?, b = 8.8508(9) ?, c = 10.7959(11) ?, β = 106.435(2)o, V = 1332.6(2) ?³, z = 4. Crystal packing revealed that compounds (1) and (2) can form dimeric structures via intermolecular H-bonding using N–H···S and N–H···N interactions, respectively. Graphical Abstract  Varying the substituent position on the pyridine ring using thiourea moieties gave unique molecular aggregations in solid state structures.      

F-type or T-type Aromatic–Aromatic Interaction in Two Isoflavone Derivatives

Abstract Two isoflavone derivatives, 5,6,7,4′-tetramethoxyisoflavone (I) and 6,4′-dimethoxy- 7-ethoxy-5-hydroxylisoflavone (II), have been synthesized and their crystal structures were determined by ¹H NMR and single crystal X-ray diffraction studies. I is triclinic, space group P-1 with a = 7.828(1) ?, b = 10.285(2) ?, c = 11.608(2) ?, α = 104.90(2)°, β = 110.546(9)°, γ = 99.54(1)° and Z = 2. II is orthorhombic, space group Pna2 ₁ with a = 7.0244(6) ?, b = 15.0104(15) ?, c = 15.7538(15) ?, and Z = 4. Molecules of I are linked into two-dimensional structure by a combination of C–H···O hydrogen bond and F-type aromatic–aromatic interactions. II shows some discrepancies with I and the molecules are linked into columns by T-type aromatic-aromatic interaction. Graphical Abstract F-type or T-type Aromatic–Aromatic Interaction in Two Isoflavone Derivatives Zun-Ting Zhang,* Xue-Ling Zhang Molecules of 5,6,7,4′-tetramethoxyisoflavone are linked into two-dimensional structure by a combination of C–H···O hydrogen bond and F-type aromatic–aromatic interactions; 6,4′-dimethoxy-7-ethoxy-5-hydroxylisoflavone shows some discrepancies with 5,6,7,4′-tetramethoxyisoflavone and the molecules are linked into columns by T-type aromatic–aromatic interaction.      

Synthesis,Crystal Structures and Thermal Analysis of Two New Silver(I)–Dithioether Lamellar Coordination Polymers

Abstract  Two new silver(I)–dithioether coordination polymers based on the self-assembly of the dithioether ligands L ^{n −R} = CH₃–S(CH₂) _n S–CH₃ (n = 1, 3) and AgX silver salts, where X = ClO₄ ⁻ (1) and PF₆ ⁻ (2), have been synthesized and characterized by single crystal X-ray diffraction and TGA. The crystallographic data of those complexes are: (1) Monoclinic P2₁/c; a = 16.5861(3) ?; b = 10.1048(2) ?; c = 15.7843(3) ?; β = 112.570(1)°; V = 2442.83(8) ?³; Z = 4. (2) Monoclinic P2₁/n; a = 8.6500(2) ?; b = 9.4053(2) ?; c = 24.0357(6) ?; β = 92.750(2)°; V = 1953.19(8) ?³; Z = 4. In both complexes, the dithioether building blocks propagated the silver(I) centers to build cationic lamellar coordination polymers, while ClO₄ ⁻ and PF₆ ⁻, which were sandwiched between silver-ligand sheets, counterbalance only the charge of the networks. The thermogravimetric investigation reveals that those complexes decompose in a single step respectively to metallic silver and silver salt. Index Abstract  Two new silver(I)–dithioether coordination polymers, obtained from the self-assembly of dithioether ligands and AgX salts with noncoordinating counteranions (X = ClO₄ ⁻ and PF₆ ⁻), were characterized by X-ray crystallography and thermogravimetric analysis (TGA).      

Synthesis and Crystal Structure of a Polymorph of the DMF Solvate of the Dicoppertetracarboxylate Paddlewheel Complex Cu<Subscript>2</Subscript>(p-aminobenzoate)<Subscript>4</Subscript>(DMF)<Subscript>2</Subscript>

Abstract  Reaction between p-aminobenzoic acid (HpABA) and Cu(NO₃)₂ · 2.5H₂O in basic MeOH/DMF affords green crystals of the dicopper paddlewheel complex, Cu₂(pABA)₄(DMF)₂ · 2DMF, 1, identified by single crystal X-ray crystallography: triclinic P-1, with a = 10.3728(2) ?, b = 10.617(2) ?, c = 11.128(2) ?, α = 81.705(3)°, β = 79.984(2)°, γ = 65.965(2)° and Z = 2. The crystal structure of 1 reveals that it is the second polymorph of Cu₂(pABA)₄(DMF)₂ · 2DMF and experiments on the stability of 1 indicate that it can be converted to Form I through desolvation followed by exposure to DMF. Graphical Abstract  Crystal structure of a polymorphic discrete dicoppertetracarboxylate is investigated for the conversion between the two forms influenced by hydrogen bonds.      

Imino-Diels-Alder Adducts. Part XIII. Polymorphism in Pyrano [3,2-c] Quinolines

Abstract Crystallization by slow evaporation of methanol solution of 5-(4-nitrophenyl)-3,4,4a5,6,10b-hexahydro-2H-pyrano[3,2-c] quinoline, yields two polymorphs. Rectangle plate-like crystals have a triclinic (P ) structure, with one molecule in the asymmetric unit, a = 8.2299(5) ?, b = 9.7774(6) ?, c = 11.0047(7) ?, α = 65.718(1)°, β = 75.699(1)° and γ = 71.617(1)°, while, long needle-like crystals exhibit a monoclinic (C2/c) crystal structure in which two independent molecules comprise the asymmetric unit, a = 32.285(3) ?, b = 9.4045(7) ?, c = 22.804(2) ? and β = 114.965(1)°. The crystal structures reveal the molecule in both the polymorphs as an endo-Imino-Diels-Alder cycloadduct isomer. The stereochemistry of the pyran ring in both the polymorphs is exo to the quinoline ring formed in the cycloaddition step. The molecules are linked by N–H···O hydrogen bonds into centrosymmetric dimers forming R₂ ²(18) rings in the triclinic form, while they are arranged to form a helical chain in the monoclinic form. Index abstract Crystallization by slow evaporation of methanol solution of 5-(4-nitrophenyl)-3,4,4a5,6,10b-hexahydro-2H-pyrano[3,2-c] quinoline, yields two polymorphs. The crystal structures reveal the molecule in both the polymorphs as an endo-Imino-Diels-Alder cycloadduct isomer. The stereochemistry of the pyran ring in both the polymorphs is exo to the quinoline ring formed in the cycloaddition step. The molecules are linked by N–H···O hydrogen bonds into centrosymmetric dimers forming R₂ ²(18) rings in the triclinic form, while they are arranged to form a helical chain in the monoclinic form. In the present study, we have determined the crystal structures of two polymorphs of pyranoquinoline, I and II.     

Synthesis and crystal structures of the bis-Schiff bases of 2-(methylthio)aniline with isophthaldehyde, terephthaldehyde, and para-diacetylbenzene

The crystal structures of the new compounds 1,3-bis(((2-methylthio)phenylimino)methyl)benzene (1), 1,4-bis(((2-methylthio)phenylimino)methyl)benzene (2), and 1,4-bis(1-((2-methylthio)phenylimino)ethyl)benzene (3) were obtained by single crystal X-ray diffraction. Compound 1 crystallizes in the orthorhombic space group Pna2₁ with a=16.8250(13) ?, b=18.1068(13) ?, c=6.3086(5) ?; and Z=4. Compound 2 crystallizes in the triclinic space group with a=6.7532(7) ?, b=9.4433(9) ?, c=15.2473(15) ?; and α=86.339(2)°, β=80.609(2)°, γ=80.962(2)°; and Z=2. Compound 3 crystallizes in the triclinic space group with a=6.787(3) ?, b=7.517(3) ?, c=10.653(4) ?; and α=89.998(7)°, β=72.341(7)°, γ=75.998(7)°; and Z=1. Details of the synthesis, structures, and spectroscopic results are discussed.     

Synthesis, Crystal Structure of a New Co(II) Complex with Pyrazine-2,3,5,6-tetracarboxylic Acid

Abstract A new complex [Co(H₂pztc)(bpy)H₂O] (H₄pztc = pyrazine-2,3,5,6-tetracarboxylic acid, bpy = 2,2′-bipyridine) has been synthesized by hydrothermal reactions of Co(NO₃)₂ · 6H₂O with H₄pztc and bpy and characterized by IR and X-ray diffraction single crystal structure analysis. It belongs to monoclinic system, P2₁/c space group with a = 13.454(2) ?, b = 12.939(2) ?, c = 11.4993(19) ?, α = 90°, β = 111.640(3)°, γ = 90°. This complex is assembled into 3D supramolecular architecture by hydrogen bonds (O–H···O, C–H···O). Index Abstract A new complex of cobalt(II) with pyrazine-2,3,5,6-tetracarboxylic acid and 2,2′-bipyridine is assembled by intermolecular hydrogen bonds forming 2D layer and 3D supramolecular network.      

Crystal Structures of Hexameric and Dimeric Complexes of Lithioisobutyrophenone

Abstract The crystal structures of two unsolvated hexameric complexes and one N,N,N′,N′-tetramethyl-1,2-ethanediamine (TMEDA)-solvated dimeric complex of the lithium enolate of 2-methyl-1-phenyl-1-propanone (lithioisobutyrophenone, LiIBP) are reported. The unsolvated LiIBP complexes crystallize from benzene-d ₆ to yield two different types of crystals that have similar structures: one in the triclinic space group P-1 with a = 10.7944(7), b = 11.9350(8), c = 12.0956(8) ?; α = 117.5560(10), β = 100.8090(10), γ = 92.3030(10)° and Z = 1 and a second in the monoclinic space group C2/c with a = 17.6011(11), b = 14.7389(9), c = 21.0943(13) ?; β = 105.2510(10)° and Z = 4. The two LiIBP hexamers differ slightly in the conformations of the enolate moieties around the Li₆O₆ core. The hexamer in both the triclinic as well as the monoclinic polymorph is located on a crystallographic inversion center that each generates the other half of the cluster. The TMEDA-solvated LiIBP dimer crystallizes from hexanes in the monoclinic space group C2/c with a = 11.8472(6), b = 14.8268(7), c = 19.2719(9) ?; β = 98.8480(10)° and Z = 4. The center of the dimer is located on a crystallographic C2 axis. These complexes represent only the second reported crystal structures of either an unsolvated hexamer or a solvated dimer of a lithium enolate of a simple monocarbonyl ketone. Graphical Abstract The X-ray crystal structures of two unsolvated hexameric and one N,N,N′,N′-tetramethyl-1,2-ethanediamine (TMEDA)-solvated complexes of the lithium enolate of 2-methyl-1-phenyl-1-propanone (lithioisobutyrophenone, LiIBP) are reported. Electronic supplementary material The online version of this article (doi: ) contains supplementary material, which is available to authorized users.     

Supramolecular Cobalt(II), Copper(II) and Cadmium(II) Complexes Obtained from a Proton Transfer Compound including Pyridine-2,6-dicarboxylate and Propane-1,3-diaminium Ions; Synthesis,Characterization and Crystal Structure

Abstract The three complexes (pnH₂)[Co(pydc)₂]·4H₂O 1, (pnH₂)[Cu(pydc)₂]·4H₂O 2, and (pnH₂)[Cd(pydc)₂]·3.5H₂O 3 (pn: propane-1,3-diamine, pydc: pyridine-2,6-dicarboxylate) were prepared using a proton transfer compound (pnH₂)(pydc)·(pydcH₂)·2.5H₂O, LH ₂ and corresponding metallic salts. The characterization was carried out using elemental analysis, IR and NMR spectroscopy, and single crystal X-ray diffraction. Complexes 1 and 2 crystallize in space group P , but complex 3 crystallizes in space group P2/c. Cell parameters of the complexes are a = 8.449(1) ?, b = 11.668(1) ?, c = 12.801(1) ?, α = 115.748(2)°, β = 93.038(2)°, γ = 97.867(2)° for 1; a = 7.973(2) ?, b = 16.632(2) ?, c = 25.280(5) ?, α = 94.178(6)°, β = 95.186(6)°, γ = 91.603(5)° for 2 and a = 20.055(1) ?, b = 13.8161(9) ?, c = 8.2418(5) ?, β = 100.086(1)° for 3. The three crystal structures illustrate that the metal ion is six-coordinated by two pydc’s. In structures of 2 and 3, it can be seen that propane-1,3-diaminium fragments have different conformations. The complexes have ion-pairing interactions, O–H···O, N–H···O and C–H···O hydrogen bonds, π–π stacking as well as van der Waals forces as the main factors in formation of their supramolecular structures. Index Abstract Supramolecular Cobalt(II), Copper(II) and Cadmium(II) Complexes Obtained from a Proton Transfer Compound including Pyridine-2,6-dicarboxylate and Propane-1,3-diaminium Ions; Synthesis, Characterization and Crystal Structure Hossein Aghabozorg, Mohammad Ghadermazi,Bahar Nakhjavan, Faranak Manteghi The synthesis, characterization, crystal structure and non-covalent interactions of three supramolecular complexes of Co(II), Cu(II) and Cd(II) obtained by the reaction of a proton transfer compound i.e. (pnH₂)(pydc)·(pydcH₂)·2.5H₂O with the corresponding metallic salts are reported. Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.     

Crystal Structures of (2-oxo-2H-Quinaxalin-1-yl)-acetic Acid and its Cobalt and Nickel Complexes and Their Comparison with (1,3-Dioxo-1,3-dihydro-isoindol-2-yl)-acetic Acid

Abstract The crystal structures of (2-oxo-2H-quinaxalin-1-yl)-acetic acid and its cobalt and nickel complexes are determined. The (2-oxo-2H-quinaxalin-1-yl)-acetic acid (1) crystallizes in orthorhombic, Pbca, a = 12.8571(11) ?, b = 9.4267(8) ?, c = 15.0095(13) ?, the cobalt complex of (2-oxo-2H-quinaxalin-1-yl)-acetic acid (2) crystallizes as dihydrate in triclinic, P-1 space group with a = 4.81150(10) ?, b = 11.8631(2) ?, c = 12.4867(3) ?, α = 71.7800(10)°, β = 79.2490(10)°, γ = 84.9020(10)° whereas the nickel complex of (2-oxo-2H-quinaxalin-1-yl)-acetic acid (3) crystallizes in monoclinic, P2₁/c space group with a = 14.9210(5) ?, b = 4.81730(10) ?, c = 15.7672(5) ?. and β = 99.823(2)°. The crystal structure of the ligand and the complexes are compared with structures of (1,3-dioxo-1,3-dihydro-isoindol-2-yl)-acetic acid and its cobalt and nickel complexes. Index Abstract The crystal structures of (2-oxo-2H-quinaxalin-1-yl)-acetic acid and its nickel and cobalt complexes are compared with (1,3-dioxo-1,3-dihydro-isoindol-2-yl)-acetic acid and its corresponding complexes with nickel(II) and cobalt(II).      

Synthesis and Structure of 2-Ferrocenylmethylidenehydrazono-1,3-dithiolane

Abstract The title compound, 2-Ferrocenylmethylidenehydrazono-1,3-dithiolane was synthesized by ferrocene- carboxaldehyde with 2-hydrazono-1,3-dithiolane and characterized by elemental analysis, ¹H NMR, IR, UV-Vis and single crystal XRD. The crystal belongs to orthorhombic, space group Fdd2 with unit cell parameters a = 27.487(4) ?, b = 35.239(6) ?, c = 6.0517(9) ?, V = 5861.7(16) ?³, Z = 16, Dc = 1.497, Mr = 330.24, μ = 1.300 mm⁻¹, F(000) = 2720, R ₁ = 0.0413, and wR ₂ = 0.0753. The molecule is the anti-rotamer of the trans-isomer and every molecule joins each other to a zig-zag chain through the intermolecular unclassical hydrogen-bonds of C(7)–H(7)···N(1) (3.449(8) ?, 172°). Further every chain self-assembles into a three-dimensional networking structure via another intermolecular unclassical hydrogen-bonds of C(1)–H(1A)···π/Cg (3.597(7) ?, 143°) and the weak inter molecular interaction forces of C(4)–H(4)···S(1) (3.742(7) ?, 139°) and C(14)–H(14)···H(6) (3.080(7) ?, 134°). Graphical Abstract Synthesis and Structure of 2-Ferrocenylmethylidenehydrazono-1,3-dithiolane Yonghong Liu, Xiangqian Dai, Xiaolan Liu, Wei Xu, and Rong Guo College of Chemistry and Chemical Engineering, Yangzhou University, Yangzhou, 225002, P.R. China The title compound was synthesized and characterized by elemental analysis, 1H NMR, 13C NMR, IR, UV-Vis and single crystal XRD.      

Synthesis and Structure of the Dimeric Copper(II) Complex Tetrakis[<Emphasis Type="Italic">N</Emphasis>-thiazol-2-yl-(4-methylphenyl)sulfonamidate]dicopper(II)

Abstract The coordination chemistry of the ligand N-thiazol-2-yl-toluenesulfonamidate towards the copper(II) ion has been investigated using an electrochemical synthesis method. The X-ray structure of this complex was elucidated and is discussed. The compound crystallised in the monoclinic crystal system, P2₁/c space group with a = 17.3888(9), b = 16.3003(9), c = 18.3679(9) ? and β = 114.3640(10)°. Four bidentate sulfathiazolato anions bridge two metal centers in a paddle-wheel fashion, with the nitrogen atoms as donors to give a dimeric species with a Cu···Cu distance of 2.7859(5) ?. Graphical Abstract The coordination chemistry of the ligand N-thiazol-2-yl-toluenesulfonamidate towards the copper(II) ion has been investigated using an electrochemical synthesis method. The X-ray structure of the product has been elucidated and is discussed. Sulfathiazolato anions act as bridging ligands to give a dimeric species with a Cu···Cu distance of 2.7859(5) ?.      

Crystal and Molecular Structures of Benzyl-(2-chloro-6-methylpyrimidin-4-yl)amine and Benzyl-(4-chloro-6-methylpyrimidin-2-yl)amine: Confirmation of Computationally Predicted Restricted Rotation

Abstract Crystal structures for the isomeric compounds benzyl-(2-chloro-6-methylpyrimidin-4-yl)amine (1), as its hemi-hydrate, and benzyl-(4-chloro-6-methylpyrimidin-2-yl)amine (2) have been determined. Conformational differences lead to multiple molecules, i.e. two and three, in their respective structures. Layers feature in each of the crystal structures and are stabilized by substantial hydrogen-bonding interactions. Compound (1) crystallizes as a hemi-hydrate in the triclinic space group P-1 with a = 8.667(5) ?, b = 11.421(7) ?, c = 12.954(8) ?, α = 78.330(10)°, β = 84.553(10)°, γ = 75.510(9)°, and Z = 4. Compound (2) crystallizes in the monoclinic space group P2₁/c with a = 10.740(3) ?, b = 21.487(6) ?, c = 14.914(4) ?, β = 95.014(5)°, and Z = 12. Index Abstract Substantial hydrogen-bonding interactions leading to layer structures feature in each of the crystal structures of the isomeric title compounds. Electronic supplementary material The online version of this article (doi: ) contains supplementary material, which is available to authorized users.     

Supramolecular Network via Hydrogen Bonding and π–π Stacking in 4,4′-Bipyridin-1-ium Perchlorate Dihydrate

Abstract The crystal structure of 4,4′-bipyridin-1-ium perchlorate dihydrate, [C₁₀H₉N₂](ClO₄) · 2H₂O, is determined by room temperature X-ray diffraction. The compound crystallizes in the triclinic space group P-1 with a = 8.122(3) ?, b = 9.726(3) ?, c = 17.648(6) ?, α = 78.181(4)°, β = 82.797(5)°, γ = 67.439(4)°, Z = 2, V = 1258.4(7) ?³. In the compound, monoprotonated 4,4′-bipyridin-1-ium cations are self-assembled into supramolecular chains along the a-axis through N–H···N hydrogen bonds in a head-to-tail fashion. The chains are stacked via π–π stacking interactions to create two-dimensional sheets. The interlayer space is occupied by the hydrogen-bonded water chains that are linked to the organic sheets via C–H···O interactions and the perchlorate anions that are linked to the water chains and the organic sheets via O–H···O and C–H···O hydrogen bonds, respectively, thus generating a three-dimensional supramolecular architecture. Index Abstract Supramolecular Network via Hydrogen Bonding and π–π Stacking in 4,4′-Bipyridin-1-ium perchlorate dihydrate Jian-Yong Zhang, Ai-Ling Cheng and En-Qing Gao* Monoprotonated 4,4′-bipyridin-1-ium cations are self-assembled into supramolecular chains along the a-axis through N–H···N hydrogen bonds, and these chains are stacked via π–π stacking and hydrogen bond interactions involving water molecules and perchlorate anions.      

Three Dimensional Network Polymeric Structure of (4,4′-bipyridinium)[CdBr<Subscript>4</Subscript>]<Subscript><Emphasis Type="Italic">n</Emphasis></Subscript>: Supramolecular Motifs and Crystal Supramolecularity

Abstract A single crystal structure determination of the complex (4,4′-bipyridinium)[CdBr₄] _n , [henceforth (I)], has been carried out. It crystallizes in the monoclinic space group C2/c, with the following cell parameters: a = 16.119(3) ?, b = 13.206(3) ?, c = 7.2601(15) ?, β = 115.62°, V = 1393.5(6) ?³, with Z = 4 formula units. The polymeric anion forms an infinite zig-zag chain of edge-sharing octahedra along c, with a distorted octahedral stereochemistry around Cd. There are N–H···Br [Br2···N1 of 3.386(13) ? and Br1···N1 of 3.363(13) ?] and C–H···Br [Br2···C5 of 3.552(16) ?] hydrogen bonding interactions, tying the CdBr chains to the cations to form 2D-network. The resulting 2D-networks are further linked by aryl···aryl (π···π) interactions within the cationic chains leading to a 3D-network. Index Abstract Three dimensional network polymeric structure of (4,4′-bipyridinium)[CdBr₄] _n : Supramolecular motifs and crystal supramolecularity. Rawhi Al-Far and Basem F. Ali The polymeric anion consists of a zig–zag chain of distorted edge shared octahedra run along c axis. The protonated cation bridges the anion chains through N–H···Br and C–H···Br into a supramolecular array.      

Crystal and Molecular Structure of <Emphasis Type="Italic">trans</Emphasis>-1,2-bis(2-benzothiazolyl)ethene

Abstract The crystal and molecular structure of trans-1,2-bis(2-benzothiazolyl)ethene is reported. Crystal data for 1: monoclinic, space group C 2/c, a = 24.926(3) ?, b = 4.843(1) ?, c = 11.164(1) ?, β = 105.274(5) °, V = 1300.0(3) ?³, and D _c = 1.50 g/cm³ for Z = 4 and R = 0.028. The molecule crystallizes in the form of a colorless plate and forms one-dimensional slipped π-stacks. Graphical Abstract The title compound crystallizes to form 1D slipped π-stacks in the solid state. Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.     

Synthesis and Crystal Structure of a Novel Double-Chain Coordination Polymer [Zn<Subscript>2</Subscript>(bipy)<Subscript>2</Subscript>(btec)(H<Subscript>2</Subscript>O)<Subscript>2</Subscript>]<Subscript>n</Subscript> (bipy = 2,2′-bipyridine; btec = 1,2,4,5-benzenetetracarboxylate)

Abstract  A novel aromatic polycarboxylate polymer, [Zn₂(bipy)₂(btec)(H₂O)₂]_n (1), has been synthesized and structurally characterized by the single crystal X-ray diffraction. Compound 1 belongs to the triclinic crystal system, space group P-1; a = 7.7449(6) ?, b = 8.9286(8) ?, c = 10.7422(8) ?, α = 80.95(1)°, β = 70.21(1)°, γ = 78.14(1)°, V = 680.93(10) ?³, Z = 2. The coordination geometry of Zn(II) atom is distorted trigonal bipyramidal with two nitrogen atoms of one 2,2′-bipy group, two oxygen atoms from two different btec ligands, and one water. The 16-membered rings are alternately arranged forming an infinite 1-D double-chain structure. A 3-D network was constructed by interlayer C···H–O, O···H–O hydrogen bonds and π–π stacking interactions. Compound 1 exhibits fluorescence at room temperature in the solid state. Graphical Abstract  A 1-D double-chain aromatic polycarboxylate polymer, [Zn₂(bipy)₂(btec)(H₂O)₂]_n (1), has been synthesized and structurally characterized by the single crystal X-ray diffraction. A 3-D network was constructed by intermolecular C···H–O, O···H–O hydrogen bonds and π–π stacking interactions. Compound 1 exhibits fluorescence at room temperature in the solid state.      

Crystal Structure of 2-Thiophenecarboxamide: A One-dimensional Tubular Structure Formed by N–H···O Hydrogen Bonds

Abstract  The crystal structure of 2-thoiphenecarboxamide is described. The compound crystallizes in the orthorhombic Pna2₁ space group with unit cell parameters a = 10.044 (3) ?, b = 14.203 (4) ? and c = 15.941 (3) ?; V = 2,274.1 (10) ?³. The asymmetric unit contains four independent molecules which are linked by N–H···O hydrogen bonds. The asymmetric unit at (x, y, z) is connected with another one, produced by the a-glide plane at 0.75 along the b-axis, that lies at (x + 0.5, −y + 1.5, z) by two N–H···O hydrogen bonds and by a C–H···O weak hydrogen bond to form a one-dimensional tube. Adjacent tubes are linked by C–H···pi interactions to form a three-dimensional framework. Graphical Abstract  The crystal structure of 2-thiophenecarboxamide, contains four crystallographically independent molecular components in the asymmetric unit linked by four N–H···O hydrogen bonds and a weak C–H···O hydrogen bond and form a one-dimensional tube. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.     

Synthesis and Structural Conformation Studies of a Potent Unsymmetrical 1,4-Dihydropyridine

Abstract 2,6-Dimethyl-5-(phenylcarbamoyl)-4-(3-nitrophenyl)-1,4-dihydropyridine-2-carboxylate was synthesized in two steps and was characterized spectroscopically and confirmed by X-ray diffraction studies. The molecule crystallizes in the monoclinic crystal class in the spacegroup P2₁/c with cell parameters a = 10.5960(6) ?, b = 10.2450(7) ?, c = 19.5790(11) ?, β = 107.448(3)° and Z = 4. The 1,4-dihydropyridine ring in the structure adopts a flattened boat conformation. Graphical Abstract 2,6-Dimethyl-5-(phenylcarbamoyl)-4-(3-nitrophenyl)-1,4-dihydropyridine-2-carboxylate was synthesized in two steps and was characterized spectroscopically and confirmed by X-ray diffraction studies. The molecule crystallizes in the monoclinic crystal class in the spacegroup P2₁/c with cell parameters a = 10.5960(6) ?, b = 10.2450(7) ?, c = 19.5790(11) ?, β = 107.448(3)° and Z = 4. The 1,4-dihydropyridine ring in the structure adopts a flattened boat conformation.