Crystal structure of cis-[Rh(biq)2Cl2]Cl·3H2O: Solid-state characterization and crystal packing analysis

The title compound, cis-[Rh(biq)₂Cl₂]Cl·3H₂O (biq = 2,2′-biquinoline) crystallized in the monoclinic space group P2 ₁ /n with a = 11.231(2) Å, b = 20.895(4) Å, c = 14.081(3) Å, β = 94.76(3)°, V = 3293.0(11) ų, D _c = 1.565 g cm⁻³, μ = 0.806 mm⁻¹, F(000) = 1576 and Z = 4. It contains a monomeric [Rh(biq)₂Cl₂]⁺ cation, a chloride ion and three molecules of H₂O. The rhodium(III) ion is hexa coordinated forming a distorted octahedral arrangement. The mean Rh(III)–N distance for the four Rh(III)–N bonds is 2.0625 Å. The two chloride atoms are bonded in a cis configuration [Rh(III)–Cl bond distances are 2.329(3) and 2.341(4) Å]. The structure shows a curling stacks of cationic complexes interacting via offset-face-to-face (OFF) π–π aryl interaction motif. Water molecules and chloride ions are hydrogen bonded (H₂O···H–OH and Cl···H–OH) and links the curling stacks by hydrogen bonding via Rh–Cl···H–OH interactions.     

Synthesis and crystal structure of anhydrous copper suberate: [Cu<Subscript>2</Subscript>(OOC-(CH<Subscript>2</Subscript>)<Subscript>6</Subscript> -COO)<Subscript>2</Subscript>]

The title compound [Cu₂(OOC-(CH₂)₆-COO)₂] was synthesized and its crystal structure has been determined by single crystal X-ray diffraction methods. The complex crystallizes in the triclinic space group P-1 with a=5.1077(5) ?, b=8.362(2) ?, c=11.378(2) ?, α=93.773(6)°, β=97.587(9)°, γ=90.493(’9)° and D _cal=1.629 mg/m³ for Z=1.  The structure is polymeric and consists of discrete anhydrous centrosymmetric binuclear units [Cu₂(OOC-(CH₂)₆-COO)₂]. The two copper(II) centres bridged by the suberate groups in a syn-syn conformation, are in pentacoordinated distorted square-pyramidal coordination environment, with an intramolecular Cu–Cu distance of 2.5793(10) ?. Each binuclear unit, related to the next through μ_oxo bridges with a Cuμ_oxo–Cuμ_oxo separation of 3.2326(10)?, defines infinite chains of one-edge sharing CuO₅ square pyramid.     

Crystal Engineering: A Salt of Mellitate Ion,MA<Superscript>−2</Superscript>, with Hydronium,H<Subscript>3</Subscript>O<Superscript>+</Superscript>, Containing π–π Stacks of Neutral Phenazine,PZ, in the Crystal

Abstract  The structure of the benznenehexacarboxylic acid (mellitic acid, MA)––phenanthroline (PL) complex (MA⁻²   2PL⁺¹) consisting of infinite stacks of phenanthroline separated for optimum π–π interactions and sandwiched between MA ribbons suggested a design of models with more significant π–π interactions to produce conducting materials. Phenazine (9,10-diazaanthracene) was considered as a promising choice. The X-ray structure of the complex (MA₁–PZ₄) from MA⁻² and neutral PZ was a major surprise since the complex was not only radically different from MA–PL but also the MA exhibited the rare direct interaction with the base PZ. In a novel arrangement, a continuous chain formed by the linking of the peri carboxylic groups of MA⁻² mediated with hydronium ions, H₃O⁺, supports a 4-fold arrangement of four phenazine molecules where four carboxylic groups are engaged in hydrogen bond formation with one of the nitrogens of each PZ. The running chain of MA⁻² supports the formation of stacks of phenazine molecules which are separated by ~3.39–3.60 ?, well suited for π–π overlap. The proximal placement of such threaded modules enables their transformation to layered stacks thus possibly enhancing their π–π interactions. Crystal structure parameters are: sp. gr. C2/c, a = 13.2819(23) ?, b = 11.3669(20) ?, c = 33.3757(57) ?, β = 96.515(3), R ₁ = 0.0521 for 4,198 data (I > 2σ(I)) and wR ₂ = 0.0828 for all 6,194 data. Graphical Abstract  Dark brown thick crystals from MA and phenazine form the sandwiched module (PZ₂–MA⁻²–PZ₂) that assembles vertically to produce infinite π–π stacks of PZ. Isabella L. Karle (Senior Scientist) is responsible for the structure analysis and discussion. Subramania Ranganathan (Professor) is responsible for design of molecule and synthesis.     

Synthesis and Crystal Structure of 5-[2-(6-bromonaphthalenyloxymethyl)]-3-(4-morpholinomethyl)-1,3,4-oxadiazole-2(3<Emphasis Type="Italic">H</Emphasis>)-thione

Abstract  The title compound, C₁₈H₁₈BrN₃O₃S, a derivative of 1,3,4-oxadiazole, crystallizes in the triclinic space group P-1 with unit cell parameters a = 6.8731(3), b = 8.9994(4), c = 15.7099(6) ?, α = 92.779(3)°, β = 130.575(3)°, γ = 107.868(4)°, Z = 2. The dihedral angle between the mean planes of the planar naphthyl and morpholine (chair) rings with the planar oxadiazol ring is 50.1(8) and 76.8(6)°, respectively. The planar naphthyl ring is twisted 52.2(5)° with the mean plane of the morpholine ring. A group of four intermolecular close contacts are observed between a bromine atom and hydrogen atoms from the closely packed naphthyl, morpholine and oxy–methyl groups in the unit cell. These molecular interactions in concert with an additional series of π–π stacking interactions that occur between the center of gravity of the two 6-membered rings of the naphthalene group influence the twist angles of each of these three groups. A MOPAC AM1 calculation of the conformation energy of the crystal structure [226.0128(9) kcal] compared to that of the minimum energy structure after geometry optimization [29.9744(1) kcal] reveals a significantly reduced value. The twist angles of the three groups above also change after the AM1 calculation giving support to the influence of both intermolecular C–H···Br short-range interactions and Cg π–π stacking interactions on these angles which therefore play a role in stabilizing crystal packing. Graphical Abstract  Crystal structure of 5-{[(6-bromonaphthalen-2-yl)oxy]methyl}-3-(morpholin-4-ylmethyl)-1,3,4-oxadiazole-2(3H)-thione, C₁₈H₁₈BrN₃O₃S, is reported and its geometric and packing parameters described and compared to a MOPAC computational calculation. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.     

Br···HN, N···HC, Br···HC, and Br···Br intermolecular interactions as supramolecular synthons: Synthesis and crystal structure of bis(2-amino-5-methylpyridinium) tetrabromomercurate(II)

The bis(2-amino-5-methylpyridinium) tetrabromomercurate(II) (C₆H₉N₂)₂[HgBr₄] salt is triclinic, P1, with the following cell parameters: a=8.060(8) ?, b=9.035(9) ?, c=14.964(10) ?, α=96.032(19)°, β=90.317(15)°, γ=113.32(2)°, V=993.8(15) ?³, with Z=2 formula units. The crystal structure consists of alternating stacks of inorganic HgBr₄ ²⁻ anions and organic layers of 2-amino-5-methylpyridinium cations parallel to c-axis. The cohesion forces that connect molecules in the organic layers are N···HC hydrogen bonding and π–π stacking. The HgBr₄ ²⁻ units in the inorganic stacks are attracted via Br···Br intermolecular interactions.Supplementary material CCDC 270395 contains the supplementary crystallographic data. These data can be obtained free of charge via www.ccdc.cam.ac.uk/data_request/cif, or by e-mailing at data_request@ccdc.cam.ac.uk, or by contacting the Cambridge Crystallographic Data Centre, 12 Union Road, Cambridge CB2 1EZ, UK; fax: + 44(0)1223-336033.     

Crystal Structure and Physical Characterisation of [Zn<Subscript>2</Subscript>(Benzoato)<Subscript>4</Subscript>(Caffeine)<Subscript>2</Subscript>]·2 Caffeine

Abstract  

The crystal structure of [Zn₂(benzoato)₄(caffeine)₂]·(caffeine)₂ was determined by direct method and Fourier technique. The structure was refined by full-matrix least-squares method to a weighted R factor of 0.0582. The structure consists of centrosymmetric dimeric units where the two zinc(II) atoms are coordinated by four bridging benzoates in a syn–syn arrangement and two caffeine ligands at the apices of a bicapped square prism. Remaining two caffeines are bound only by hydrogen bonds. The Zn–Zn distance is 2.961(1) ?. The Zn(II) atoms are displaced by 0.365 ? from the basal plane containing four oxygen atoms towards the apical caffeine molecules. The dimeric structure of the complex is consistent with spectrum and thermal data. The structural data are compared with those found in similar [Zn₂(RCOO)₄(NL)₂] complexes.     

Synthesis and crystal structure of Mn(II) and Zn(II) complexes with 1,3,5-tris(carboxymethoxyl)benzene ligand

Two complexes (H₂bipy)[M₂(TB)₂(H₂O)₈]·5H₂O (M = Mn 1, Zn 2) (bipy = 4,4′-bipyridine, H₃TB = 1,3,5-tris(carboxymethoxyl)benzene) were synthesized by the reaction of the corresponding metal salt with ligand H₃TB and 4,4′-bipy in an aqueous methanol solution at room temperature, respectively. Their structures were determined by single crystal X-ray diffraction analysis. Both complexes 1 and 2 crystallize in the triclinic space group with the crystal parameters of 1: a = 9.725(12) ?, b = 10.651(13) ?, c = 10.882(13) ?, α = 91.72(2)°, β = 96.41(2)°, γ = 97.72(2)°, V = 1109(2) ?³, Z = 1 and 2: a = 9.610(10) ?, b = 10.55(2) ?, c = 10.83(2) ?, α = 91.60(4)°, β = 95.32(2)°, γ = 97.73(4)°, V = 1082(3) ?³, Z = 1. Complexes 1 and 2 have the same dinuclear structure, in which each metal atom is six coordinated with distorted octahedral geometry by two oxygen atoms from two different TB³⁻ ligands and four ones from four coordinated water molecules. The dinuclear units are further linked by hydrogen bonding and π–π interactions to form the three-dimensional framework structure.     

The co-crystal of iron(II) complex hydrate with hydroxybenzoic acid: [Fe(Phen)<Subscript>3</Subscript>]Cl(p-hydroxybenzoate).2(p-hydroxybenzoic acid).7H<Subscript>2</Subscript>O

Crystal of [Fe(Phen)₃]Cl(PHB).2(PHBH).7H₂O (1) is triclinic, space group P-1 with a = 12.0388(11) ?, b = 15.5286(14) ?, c = 15.7794(14) ?, α = 89.759(2)°, β = 75.818(2)°, γ = 71.900(2)° and Z = 2, (phen = phenanthroline, PHBH = p-hydroxybenzoic acid, PHB = p-hydroxybenzoate anion). The phen in adjacent Fe(phen)₃ ²⁺ cations are π–π interacted forming offset face to face (OFF) motifs. Juxtaposition of four phen ligands from two cations encapsulate an R₂ ²(8) dimeric unit of H-bonded PHBH molecules within a centrosymmetric box froming a filled aryl box motif (FAB). Alternation of OFF and FAB motifs form {OFF⋯FAB}∞ strands. The Fe(phen)₃ ²⁺ cation engages its phen ligands in π–π and/or CH–π interactions with two crystalographically different PHBH molecules and one PHB anion. Seven water molecules and a chloride anion per iron(II) trisphenanthroline cation fill empty spaces in the structure forming a hydrophilic cluster. Extensive intermolecular H-bond interactions occur between water molecules, chloride anions, PHBH molecules, and PHB anions. Thermal analysis of (1) was done under N_2(g). The TG, and dTG curves revealed the expected mass losses. All associated processes are endothermic as shown in the DSC curve.     

Hydrogen bonds and π–π stacking interaction in 4′, 7-dimethoxylisoflavone and 4′,7-diacetyl-O-isoflavone

4′,7-dimethoxylisoflavone, C₁₇H₁₄O₄, (I), is linked into a supramolecular structure by a variety of weak but direction-specific intermolecular forces, the molecules are linked into chains through C–H⋅sO hydrogen bonds, these chains are further linked by face-to-face (F-tape) π–π stacking into a one-dimensional bi-chain, another type π–π stacking, edge-to-face (T-tape), assemble the bi-chain into framework together with C–H⋅sO hydrogen bonds. 4′,7-diacetyl-O-isoflavone, C₁₉H₁₅O₆, (II), shows some discrepancies with I and the molecules are assembled into framework all by C–H⋅sO hydrogen bonds. The molecules are linked into centrosymmetric dimers built from classic R₂² (8) rings by pairs of C–H⋅sO hydrogen bonds, the dimers are linked into (011) sheets by combination of the R₂² (8) ring and C–H⋅sO hydrogen bonds, another C–H⋅sO hydrogen bond assemble the sheets into three-dimensional network.     

Synthesis and Single Crystal X-Ray Structure of [Na(H2O)2(C18H15O6SO3)]2

Abstract  [Na(H₂O)₂(C₁₈H₁₅O₆SO₃)]₂ was synthesized by sulfated 5-hydroxy-6,7,4′-trimethoxyisoflavone with concentrated sulfuric acid. Single-crystal X-ray diffraction study indicates that it is a dimeric centrosymmetric species. The coordination polyhedron of each Na(I) atom exhibits a distorted trigonal bipyramidal geometry. The dimeric units are linked by intermolecular hydrogen bonds C–H⋯π, C–H⋯O and O–H⋯O to result in a three-dimensional framework. Graphical Abstract  [Na(H₂O)₂(C₁₈H₁₅O₆SO₃)]₂ was synthesized by sulfated 5-hydroxy-6,7,4′-trimethoxyisoflavone with concentrated sulfuric acid. The coordination polyhedron of each Na(I) atom exhibits a distorted trigonal bipyramidal geometry. The dimeric centrosymmetric units are linked by intermolecular hydrogen bonds C–H⋯π, C–H⋯O and O–H⋯O to result in a three-dimensional framework. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.     

A supramolecular structure of bis(1,3-diphenyl-1,3-propanedionato-O,O′) (1,10-phenanthroline-N,N′)cobalt(II) based on C–H…O, C–H…π and π…π interactions

The compound bis(1,3-diphenyl-1,3-propanedionato-O,O′) (1,10-phenanthroline-N, N′)cobalt(II) (Co(DBM)₂(1,10-phe)) was investigated as a potential host component for functional inclusion materials. The molecules of the complex in the crystal (a=21.015(5) ?, b=17.456(5) ?, c=9.503(3) ?, β=107.04(2)°, s.g. C 2/c) are centrosymmetric and assemble by way of C–H···O and C–H···π hydrogen bonds as well as π···π stacking interactions to provide a supramolecular ladder-like motif that is accompanied by a variant of the six phenyl-embrace synthon.     

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.      

Synthesis and crystal structure of Cu3(Bipy)2(L1)2(L2)2? 4H2O(Bipy = 2,2′-bipyridine, L1 =1-((2-sulfonateethylimino)methyl)-2-naphthol), L2 = 2-hydroxy-1-naphthaldehyde)

The title compound, Cu₃(Bipy)₂(L¹)₂(L²)₂⋅4H₂O, was synthesized in the methanol solution of Bipy and Cu(II) in the presence of 1-((2-sulfonate-ethylimino)-methyl)-2-naphthol (L¹), which was condensation compound of taurine and 2-hydroxy-1-naphthaldehyde. This complex crystallized in the space group P-1 with a = 9.825(2) ?, b = 12.626(2) ?, c = 14.342(3) ?, α = 90.29(1)^∘, β = 100.67(1)^∘, γ = 101.67(2)^∘, and Z = 2. In the trinuclear Cu(II) complex, there are two type Cu atoms which have square and square pyramid geometries, respectively. The Cu–N distances vary from 1.965(3) to 2.000(4) ?, while the Cu–O distances are between 1.896(3) and 2.337(4) ?.     

Synthesis and Crystal Structure of a New Schiff Base 4-[(2-hydroxy-benzylidene)-amino]-<Emphasis Type="Italic">N</Emphasis>-(5-methyl-isoxazol-3-yl)-benzenesulfonamide

Abstract  The structure of the title compound (C₁₇H₁₅N₃O₄S)₂ the schiff base, bis(N-(5-methyl-3-isoxazolyl)-4-[(2-hydroxy benzylidene)-amino]) benzene sulfonamide was elucidated by H¹, C¹³ NMR, UV–VIS and IR spectroscopic techniques. The X-ray structure was determined in order to establish the conformation of the molecule. The compound crystallizes in the triclinic space group P-1, with a = 11.419(1), b = 11.426(0), c = 13.316(1) ?, α = 71.94(2), β = 89.79(1), γ = 89.14(2)° and Z = 4. Two benzene rings and azomethine group are practically coplanar, as a result of intramolecular hydrogen bonds involving the hydroxy O atom and azomethine N atom. The component species further interact via N–H···N and C–H···O hydrogen bonds and π–π stacking interactions. Index Abstract  The title compound (C₁₇H₁₅N₃O₄S)₂, Schiff base, bis(N-(5-methyl-3-isoxazolyl)-4-[(2-hydroxy benzylidene)-amino]) benzene sulfonamide was synthesized by the condensation of 4-amino-N-(5-methyl-3-isoxazolyl) benzene sulfonamide (SMZ) and 2-hydroxy benzaldehyde (SA). Its structure was confirmed by single crystal X-ray diffraction analysis. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.     

Intermolecular interactions involved in the crystal structure of 2-amino-5-methylpyridinium hexabromostannate (IV), (C<Subscript>6</Subscript>H<Subscript>9</Subscript>N<Subscript>2</Subscript>)<Subscript>2</Subscript>[SnBr<Subscript>6</Subscript>]

The salt bis(2-amino-5-methylpyridinium) hexabromostannate(IV) (C₆H₉N₂)₂[SnBr₆] is monoclinic, P2 ₁ /c, with the following cell parameters: a=9.1636(18) ?, b=28.767(7) ?, c=16.956(17) ?, β=101.008(5)°, V=4387.5(17) ?³, Z=8, formula units. X-ray crystallography revealed that the structure can be regarded as a semi-regular three-dimensional array of anions, with pairs of cations forming layers perpendicular to b axis in the cavities between the anions. The cohesion forces that connects molecules in the organic layers are hydrophilic N⋯HCH₂ and HN⋯HN hydrogen bonding as well as hydrophobic π-π stacking and CH₃⋯π interactions. Cations and anions are connected via strong Br⋯H hydrogen bonding. Supplementary material CCDC 276493 contains the supplementary crystallographic data. These data can be obtained free of charge via www.ccdc. cam.ac.uk/data_request/cif, by e-mailing data_ request@ccdc.cam.ac.uk, or by contacting The Cambridge Crystallographic Data Centre, 12 Union Road, Cambridge CB2 1EZ, UK; fax: +44(0)1223-336033.     

Synthesis,Characterization, and Crystal Structure of <Emphasis Type="Italic">N</Emphasis>-<Emphasis Type="Italic">p</Emphasis>-Bromophenyl-<Emphasis Type="Italic">N</Emphasis>′-Phenylacetylthiourea

Abstract   N-p-bromophenyl-N′-phenylacetylthiourea was characterized by elemental analysis, IR and ¹H NMR etc. Single crystal structure of the title compound was determined on X-ray diffraction instrument. The title compound crystallizes in monoclinic space group c2/c, with a = 21.442(5) ?, b = 12.208(2) ?, c = 11.955(2) ?, β = 109.375(4)°, and D _calc = 1.571 g/cm³ for Z = 8. An intermolecular hydrogen bond N–H···S which links two thiourea molecules as a dimer and an offset face-to-face π–π stacking interaction were observed in the title compound. The strong non-covalent interaction influences the conformation and property of thiourea derivatives. Index Abstract  The title compound, N-p-bromophenyl-N′-phenylacetylthiourea, was synthesized by the treatment of phenylacetyl chloride with 4-bromoaniline and its crystal structure determined. Single crystal X-ray diffraction analysis reveals that hydrogen bonds and face-to-face π–π stacking interactions have strong influence on the conformation and molecular stacking of the title compound.      

Self-Assembled Hydrogen-Bonding Chains of Copper(II) 2-Nitrobenzoate with Nicotinamide

Abstract  

The synthesis, spectral characterization and crystal structure of two new nitrobenzoatocopper(II) complexes, namely, [Cu₂(2-O₂Nbz)₄(nia)₂]·ACN (1) and [Cu₂(2-O₂Nbz)₄(ACN)₂] (2) (where 2-O₂Nbz = 2-nitrobenzoate, nia = nicotinamide and ACN = acetonitrile) are reported. The complexes 1 and 2 form dinuclear units of the paddle-wheel type around the crystallographic inversion centers. The copper ions are bridged by four 2-nitrobenzoate anions and the neutral N-donor ligands, viz. nicotinamide in 1 and acetonitrile in 2, are coordinated at apical positions. Selected geometric parameters of both complexes are compared with values for related tetra-2-nitrobenzoate complexes of copper(II) as well as the other dimeric copper(II) carboxylates with apical nicotinamide and acetonitrile ligands. The molecules of 1 are linked with N–H···O and C–H···O hydrogen bonds. The π–π stacking interactions in 1 are observed between benzene rings of 2-nitrobenzoate anions and pyridine rings of nicotinamide and also between acetonitrile molecules and benzene rings of 2-nitrobenzoate anions. The C–H···O hydrogen-bonds and CH/π interactions are observed in crystal structure of 2.     

Synthesis and crystal structure of the copper(I) complex with 2-[(o-pyridyl)-sulfanylmethyl]-pyrimidine ligand

The reaction of a flexible monothioether ligand, 2-[(o-pyridyl)-sulfanylmethyl]-pyrimidine (L), with CuI leads to the formation of a novel complex [Cu₄I₄(L)₂] (1), which has been characterized by elemental analyses, IR spectroscopy, and single-crystal X-ray diffraction analysis: monoclinic, space group P2₁/n, with a = 10.921(5), b = 10.824(5), c = 13.128(6) Å, β = 109.333(5)° and Z = 2. Single-crystal X-ray analyses show that complex 1 is tetranuclear structure with a distorted chair-like Cu₄I₄ skeleton. Cu···Cu interactions are found to exist in this tetranuclear molecule. In the packing mode of complex 1, there exist N⋯⋯⋯I weak interactions and intermolecular π–π contacts. These weak interactions not only stabilize the structure of complex, but also further link the tetranuclear molecules into a high-dimensional supramolecular architecture.     

Syntheses and Crystal Structures of Two Apigenin Alkylation Derivatives

Abstract Two apigenin alkylation derivatives, 4′,7-dimethoxyl-5-hydroxyflavone (I) and 4′,7-diethoxyl-5-hydroxyflavone (II), have been synthesized and their crystal structures were determined by ¹H NMR and single crystal X-ray diffraction study. (I) is triclinic, space group P−1 with a = 7.120(5) ?, b = 7.297(5) ?, c = 13.559(10) ?, α = 89.313(12)°, β = 86.298(12)°, γ = 83.999(13)° and Z = 2. (II) is monoclinic, space group P 2₁ /c with a = 16. 309(4) ?, b = 7.303(2) ?, c = 15.185(4) ?, α = 90.00°, β = 115.70(2)°, γ = 90.00° and Z = 4. They have the same flavone skeleton which is composed of a benzopyranone moiety and a phenyl moiety. Molecules of (I) are linked into a two-dimensional network by a combination of C–H···O hydrogen bond and π–π stacking interactions. (II) shows some discrepancies with (I) and the molecules are linked into a column by π–π stacking interaction. Graphical Abstract Two apigenin alkylation derivatives, 4′,7-dimethoxyl-5-hydroxyflavone (I) and 4′,7-diethoxyl-5-hydroxyflavone (II) were synthesized and their crystal structures were determined by single-crystal X-ray diffraction. Hydrogen bonding and π–π stacking interactions assemble (I) into a two-dimensional network, and in the crystal structure of (II), π–π stacking interaction leads to the formation of a column.      

Crystal Structure of Tetrakis Imidazole Copper(II) Diadipate Complex

Abstract  The title compound, [Cu(C₃H₄N₂)₄(COO–(CH₂)₄–COOH)₂] is a neutral complex and exist as a monomeric unit. The Cu atom occupies at the center of symmetry (0, 0.5, 0) with a distorted octahedral geometry. Imidazole nitrogens N1 and N6 (Cu1–N1 = 1.993(3) ?; Cu1–N6 = 2.008(3) ?) from two different imidazole group which are symmetrically disposed provides the square base and the long carboxylate oxygens (Cu1–O2 = 2.582(3) ?) from the protonated end of symmetrically oriented dibasic acid at the trans axial position. The adipate monoanion is in weak coordination with the metal center via monodentate fashion. The strong carboxylate-carboxylic acid intermolecular O–H…O interaction between the adjacent molecules is present in this structure as observed in the crystal structure of hexanedioic acid is noteworthy. In addition to the O–H…O H-bonding other molecular interactions such as N–H…O and C–H…O in packing generates a 3-D hydrogen bond network. Graphical Abstract  The title compound tetrakis imidazole Cu(II) diadipate is a neutral complex and exist as a monomeric unit with the metal atom occupies at the center of symmetry. Strong inter and intramolecular H-bonding interactions such as O–H…O, N–H…O and C–H…O in packing generates a 3-D hydrogen bond network.