Crystallographic and conformational analyses of zwitterionic form of (<Emphasis Type="Italic">E</Emphasis>)-2-methoxy-6-[(2-morpholinoethylimino)methyl]phenolate

The single crystal X-ray diffraction analysis of the title compound, C₁₄H₂₀N₂O₃, reveals that the structure is adapted to its zwitterionic form and centrosymmetric dimers are formed by N⁺–H···O⁻ type ionic weak hydrogen bonds in the crystal structure. The title compound crystallizes in the triclinic space group P−1 with a = 5.9255(13) ?, b = 9.853(3) ?, c = 12.248(3) ?, α = 101.793(19)°, β = 94.941(17)°, γ = 104.36(2)°, Z = 2, D_x = 1.308 g/cm³, μ (Mo-K_α) = 0.092 mm⁻¹. The structure was solved by direct methods and refined to a final R = 0.0371 for 2183 reflections with I > 2σ (I). The crystal structure is stabilized by N⁺–H···O⁻ type intra-molecular hydrogen bonds and N⁺–H···O⁻ type packing interactions referred to as weak hydrogen bonds. To elucidate conformational flexibility of the title molecule, the selected torsion angle is varied from −180° to +180° in every 10° separately and then molecular energy profile is calculated and construed. In addition, charge-population analysis of the crystallographically observed structure confirms its zwitterionic form.     

Crystallographic and conformational analysis of 1,3-bis(2,4-dimethoxyphenyl)imidazolidine-2-thione

The molecular and crystal structures of the title compound, C₁₉H₂₂N₂O₄S, were determined by single crystal X-ray diffraction technique. The title compound crystallizes in space group F d d 2, with a = 30.785(3) ?, b = 10.6455(9) ?, c = 11.0036(8) ?, Z = 8, D _calc = 1.379(2) g cm⁻³, μ(Mo-K_α) = 0.207 mm⁻¹, and its crystal system is orthorhombic. The structure was solved by direct methods and refined to a final R = 0.042 for 1530 reflections with I > 2σ (I). There is a half-independent molecule in the asymmetric unit. The title molecule has twofold rotational symmetry along with the C–S bond. Classically no hydrogen bond is found in the crystal structure. The crystal structure is stabilized by π–π stacking and edge to face (C–H…π-ring) interactions. To elucidate conformational features and steric hindrances of the title molecule, selected torsion angle is varied from −180° to +180° in every 10° and thus molecular energy profile is calculated by PM3 semi-empirical method.Supplementary materials CCDC 261789 contains the supplementary crystallographic data for this paper. These data can be obtained free of charge via www.ccdc.cam.ac.uk/data_request/cif, by emailing data_request@ccdc.cam.ac.uk, or by contacting The Cambridge Crystallographic Data Centre, 12, Union Road, Cambridge CB2 1EZ, UK; fax: $+$44 1223 336033.     

PM3 semiempirical study and its comparison with X-ray crystal structure of 4-[2-Methyl-4-(4-methoxyphenylazo)] phenoxyphtalonitrile

  The molecular and crystal structures of the title compound, C₂₂H₁₆N₄O₂, were determined by single crystal X-ray diffraction technique. The title compound crystallizes in monoclinic space group P1 2 ₁ /n1, with a=12.7811(9) ?, b=8.2002(4) ?, c=17.8772(14) ?, Z=4, D _calc=1.3112(1) g/cm³, μ (Mo-K_α)=0.087 mm⁻¹. The structure was solved by direct methods and refined to a final R=0.056 for 1891 reflections with I > 2σ (I). The asymmetric unit in the crystal structure contains only one neutral molecule. The positions of nitrogen atoms in the azo groups were disordered. There is no classic hydrogen bond in the crystal structure. The molecules in the crystal structure are stacked by π–π stacking and one edge-to-face interactions. In order to determine conformational flexibility and crystal packing effects on the molecules, molecular energy profile of the title compound was obtained with respect to the selected torsion angle, which is varied from −180° to +180° in every 10° via PM3 semi-empirical method.     

Crystal structure of 3β-acetoxy-17α-hydroxy-16α-methylallopregnan-20-one hemihydrate

3β-Acetoxy-17α-hydroxy-16α-methylallopregnan-20-one, C₂₄H₃₈O₄·0.5H₂O, is an intermediate towards the synthesis of dexamethasone, an important corticosteroid. The compound crystallizes in the monoclinic space group C2 with unit cell parameters: a = 10.665(2) ?, b = 7.497(1) ?, c = 28.200(4) ?, β = 92.74(2)°, Z = 4. The crystal structure has been solved by direct methods and refined to R = 0.0419 for 1579 observed reflections. All rings of the steroid skeleton are trans connected. Rings A, B, and C are all in the chair conformation. Ring D is in envelop conformation. The acetoxy and acetyl substituents are twisted with respect to the average molecular plane of the steroid. The twist along the length of the steroid molecule is negligible [C19–C10···C13–C18 = 2.3°]. In the crystal structure, the water molecule lies on a twofold axis which links the molecules into infinite supramolecular chains through OW–H···O and O–H···OW hydrogen bonds.     

The Crystal and Molecular Structure of a Polymorph and a Pseudo-Polymorph of Droperidol

Abstract Crystals of two crystal modifications of droperidol: a hemihydrate (1) and the z polymorph (2), have been isolated and their structure determined using X-ray diffraction methods. Droperidol hemihydrate crystallized in the triclinic space group P − 1, with unit cell parameters a = 6.2842(15), b = 10.1473(8), c = 16.1850(2) ?; α = 102.554(9); β = 91.917(14); γ = 99.316(12)°; V = 991.6(3) ?³, and Z = 2. The droperidol z polymorph crystallized in the monoclinic space group P2₁/c, with unit cell parameters a = 20.0406(8), b = 7.4955(4), c = 12.9733(5) ?; β = 98.089(2)°; V = 1929.39(15) ?³, and Z = 4. In 1 and 2 two molecules of droperidol are joined by two N–H···O hydrogen bonds. The structure of 1 shows a possible additional hydrogen bond linking the two droperidol molecules via the water molecule. Graphical Abstract The crystal and molecular structure of a polymorph and a pseudo-polymorph of droperidol A. Actins, R. Arajs, S. Belakovs, L. Orola, and M. V. Veidis Crystals of two crystal modifications of droperidol: a hemihydrate and the z polymorph have been isolated and their structure determined using single crystal X-ray diffraction methods. Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.     

Crystal and Molecular Structure of 6,6′-Dimethoxy-gossypol:Acetic acid (1:1)

Abstract By crystallization from dilute solutions of acetic acid (2–4%) in diethyl ether, acetone, or methyl ethyl ketone, 6,6′-dimethoxy-gossypol forms a solvate with acetic acid in a one-to-one molar ratio. The compound crystallizes in the triclinic P space group and has unit cell dimensions of a = 7.5793(10) ?, b = 14.7211(19) ? and c = 14.740(2) ?, α = 106.260(3)°, β = 102.310(3)°, γ = 95.975(3)°, Z = 2. The structure was solved by direct methods and refined to an R1 value of 0.0394 on 4252 observed reflections. Enantiomeric pairs of dimethoxy-gossypol molecules form centrosymmetic dimers that are characterized by a pair of intermolecular hydrogen bonds and by hydrophobic stacking between pairs of naphthalene rings. The acetic acid molecule accepts a hydrogen bond from a gossypol hydroxyl group and donates to a hydrogen bond with one of the aldehyde groups of an adjacent gossypol molecule. Although there is less hydrogen bonding in this structure than in the gossypol:acetic acid (1:1) structure, the molecular packing of the two compounds is similar. Graphical abstract Crystal and molecular structure of 6,6′-dimethoxy-gossypol:acetic acid (1:1) Michael K. Dowd and Edwin D. Stevens The molecular structure of the acetic acid solvate of 6,6′-dimethoxy-gossypol is presented.      

X-ray structure analysis of 1-(4-bromophenyl)-3-(4-chlorophenyl)-prop-2-en-1-one

The title compound crystallizes in the monoclinic space group P2₁/c with unit cell parameters a = 15.6239(15) ?, b = 14.0537(14) ?, c = 5.8396(5) ?, β = 92.666(3)°, V = 1280.8 (2) ?³, and Z = 4. The final reliability index is 0.0538 for 2921 observed reflections. Two phenyl rings of the title molecule are not coplanar, with a dihedral angle of 46.3(0)°. The molecular planarity of this substituted chalcone is strongly affected by the 4′-bromo group. The crystal cohesion is accentuated by π···π, C–H···Br interactions and R₃ ¹ (11) hydrogen bond.     

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.     

Structural Consequences of Anomeric Effect in 1,3,6,8-tetraazatricyclo[4.3.1.13,8]undecan-1-ium pentachlorophenolate monohydrate

Abstract  

The asymmetric unit of the crystal structure contains one molecule of the title compound and one molecule of water. X-ray diffraction spectrum of the ammonium salt of title compound exhibits deviations from the ideal molecular geometry which is explained on the basis of anomeric effect. This conclusion is consistent with the natural bond orbital analysis at the B3LYP/6-311+G** level of the anomeric effect. The molecules are linked via N–H···O hydrogen bonds. This compound crystallizes in monoclinic symmetry, in space group P2 _1/n , with lattice constants: a = 12.3850(2) ?, b = 6.8123(1) ?, c = 19.6208(4) ?, α = 90°, β = 94.864(2)°, γ = 90°, V = 1649.45(5) ?³, Z = 4, F(000) = 896, R ₁ = 3.3%, wR ₂ = 10.6%.     

Experimental and Semi-Empirical and DFT Calculational Studies on (<Emphasis Type="Italic">E</Emphasis>)-2-[(2,4-Dichlorophenylimino) methyl]-<Emphasis Type="Italic">p</Emphasis>-cresol

Abstract  

The molecular and crystal structure of the title compound, C₁₄H₁₁Cl₂NO, has been determined by X-ray single crystal diffraction technique. The compound crystallizes in the orthorhombic, space group Pbca with unit cell dimensions a = 7.5537(10) ?, b = 11.5518(13) ?, c = 29.760(4) ?, M _r  = 280.14, V = 2596.8(6) ?³, Z = 8, R ₁ = 0.065 and wR ₂ = 0.191. The title compound exists in the enol–imine tautomeric form with a strong intramolecular O–H···N hydrogen bond. The dihedral angle between the two benzene rings is 37.66(15)°. The asymmetric unit in the crystal structure contains only one neutral molecule. Calculational studies were performed by using AM1, PM3, PM6 semi-empirical and DFT methods. Geometry optimizations of compound have been carried out by using three semi-empirical methods and DFT method and bond lengths, bond and torsion angles of title compound have been determined. Dipole moments (Debye) and the energy parameters of compound (kcal/mol) were calculated by using above mentioned calculation methods. Atomic charge distribution has been obtained from AM1, PM3, PM6 and DFT. In order to determine conformational flexibility on the molecule, molecular energy profile of the title compound was obtained with respect to the selected torsion angle T(N1–C7–C1–C2), which is varied from −180° to +180° in every 10 via PM3 semi-empirical method.     

Crystal Structure of [4-(Methylsulfanyl)Phenyl]Acetic Acid

Abstract  

The title compound, C₉H₁₀O₂S, (I), crystallizes in the triclinic space group, P − 1, with unit cell parameters a = 6.2249(3), b = 7.3733(5), c = 19.5708(12), Å, α = 86.746(5)°, β = 88.682(5)°, γ = 86.988(5)°, Z = 4. The molecule consists of a methyl sulfanyl group bonded to benzyl acetic acid at the 4 position crystallizing with two molecules in the asymmetric unit. The carboxylic acid group from the acetic acid moiety in these two molecules forms a classic O–H···O hydrogen bonded dimer with O···O distances of 2.673(2) and 2.646(2) Å, in a R₂² (8) graph-set motif which link the molecules into pairs around inversion centers in the unit cell. The dihedral angles between the mean planes of the R₂² (8) graph-set motif with the mean planes of the two nearby benzyl groups within the same dimer in the unit cell are 64.1(6)° and 71.3(4)°, respectively. Within the same dimer the dihedral angle between the two benzyl groups is 45.2(1)°. The structure is supported by a weak intermolecular C–H···Cg π-ring interaction and gives support to molecular packing stability in the unit cell. Comparison to a MOPAC AM1 computational calculation provides support to these observations.     

Preparation and crystal structure of a quadruply bonded dimolybdenum complex with trans-crotonate ligands

A quadruply bonded dimolybdenum complex with trans-crotonate ligands, Mo₂(O₂CC₃H₅)₄, was synthesized and characterized by UV–VIS, IR, and NMR spectra. The crystal structure was determined by an X-ray single crystal diffraction analysis. The title complex (C₁₆H₂₀O₈Mo₂, M _w = 532.2) crystallized in the triclinic space group P-1 with the following crystallographic parameters: a = 10.236(2) ?, b = 10.393(2) ?, c = 10.524(2) ?, α = 89.59(1)°, β = 73.34(1)°, γ = 70.78(2)°, V = 1008.1(3) ?³, Z = 2, D _c = 1.753 Mg m⁻³, μ(Mo Kα = 0.71073 ?, F(000) = 528, and final R ₁ = 0.041, wR ₂ = 0.114 for observed reflections 2889 (I > 2σ(I)). The Mo₂ ⁴⁺ unit was surrounded by four trans-crotonate ligands resulting in a paddle wheel structure with one disordered trans-crotonate ligand. Molecules are bonded together by means of interactions consisting of the donation of lone pairs of electron on carboxylate O atoms on one molecule to the Mo atom on an adjacent complex. A new pattern of intermolecular bonding is observed.     

Synthesis and Crystal Structure of a New Mo(V) Complex of Cyano Ligands

Abstract  A new complex, [H₃teta][Mo(CN)₈] · H₂O, (teta = 5,7,7,12,14,14-hexamethyl-1,4,8,11-tetra-azacyocloteradeca-4,11-diene), has been synthesized and characterized by IR spectrum, element analysis and single crystal X-ray diffraction: monoclinic, space group P2(1)/c with a = 10.8553(8) ?, b = 12.4854(8) ?, c = 22.6348(15) ?, α = 90.00°, β = 97.3080(10)°, γ = 90.00°, Mr = 609.63, v = 3042.8(4), Z = 4. There are one [H₃teta]³⁺, one [Mo(CN)₈]³⁻ and one water molecule in the asymmetric unit. The complex is interconnected through hydrogen bond and formed into a 3D porous network. Graphical Abstract  A new complex, [H₃teta][Mo(CN)₈] · H₂O, has been synthesized and characterized by IR spectrum, element analysis and single crystal X-ray diffraction. And it shows a 3D porous network through hydrogen bonds.      

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 a Copper Complex of a Macrocyclic Ligand with Dissimilar HN+N(Amino)O2 and N2(Imino)O2 Inners

Abstract The copper complex [Cu(C₂₃H₂₇Br₂N₄O₂)(H₂O)(NO₃)]₂ was synthesized and characterized by X-ray diffraction. The complex crystallizes in the triclinic system with space group P-1, lattice parameters: a = 13.2293(18) (?), b = 14.184(20) (?), c = 16.522(23) (?), α = 91.923(2)°, β = 111.777(2)°, γ = 111.259(2)°, V = 2632.0(6) ?³, Z = 4, D _c = 0.88 Mg m⁻³. In the title compound [Cu(C₂₃H₂₇Br₂N₄O₂)(H₂O)(NO₃)]₂, the coordination polyhedron of the Cu atom is a square-planar environment. The structure consists of mononuclear units in which the copper(II) ions are linked in the plane by N, N′ iminato and O, O′ phenoxo atoms. In addition the crystal lattice contains one water molecule per unit. Graphical Abstract Dissymmetric ligand was efficiently synthesized and used to prepfsare a copper(II) complex which was characterized by X-ray diffraction      

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.      

C–H···π and C=O···π Intermolecular Interactions in Dibenzyl-3,6-dimethylpyrazine-2,5-dicarboxylate

Abstract A new pyrazine compound, has been synthesised and characterised by single-crystal X-ray diffraction: monoclinic, P2₁/c with a = 11.0707(3) ?, b = 5.23700(10) ?, c = 16.6997(5) ?, β = 103.5385(16)°, Mr = 376.40, V = 941.30(4) ?³, Z = 2. Each molecule possesses C _i symmetry with the two halves of the molecule related by an inversion centre. C–H···π and C=O···π interactions held the molecules together. Index Abstract C–H···π and C=O···π intermolecular interactions in dibenzyl-3,6-dimethylpyrazine-2,5-dicarboxylate Joana A. Silva, Ana C. Santos, Ana T. Marques, Manuela Ramos Silva, Ana Matos Beja, Abílio J. F. N. Sobrala In dibenzyl-3,6-dimethylpyrazine-2,5-dicarboxylate, each molecule possesses C _i symmetry. The molecules are assembled in chains via carbonyl···π interactions. Electronic supplementary material The online version of this article (doi: ) contains supplementary material, which is available to authorized users.     

Synthesis and Crystal Structure of Bis (Tetrabutylammonium)(4,4′-Azodi(phenylcyanamide)) Salt · [(<Emphasis Type="Italic">n</Emphasis>-Bu)<Subscript>4</Subscript>N]<Subscript>2</Subscript>[Azodicyd<Superscript>2−</Superscript>] · H<Subscript>2</Subscript>O

Abstract The chemical preparation and crystal structure for a 4,4′-azodi(phenylcyanamide) salt) in the solid state are reported. This compound crystallizes in the triclinic space group P with the following unit cell parameters: a = 9.759(3) ?, b = 11.237(4) ?, c = 11.919(4) ?, α = 95.54(3)°, β = 98.50(3)°, γ = 109.39(2)°, Z = 1 and V = 1204.4(7) ?³. The 4,4′-azodi(phenylcyanamide) dianion, azodicyd²⁻, is approximately planar, with the cyanamide groups (–N=C=N) in an anti conformation relative to each other and the azo group (–N=N–) adopting the more thermodynamically stable trans conformation. The crystal X-ray analysis shows that there are one azo molecule cation, two tetrabutylammonium cations and one water molecule in unit cell. Intermolecular O–H···N hydrogen bonds may be effective in the stabilization of the crystal structure of this compound and to form linear chain structure in the packing. Index Abstract Synthesis and crystal structure of Bis (Tetrabutylammonium)(4,4′-Azodi(phenylcyanamide)) salt . [(n-Bu)4N]2[Azodicyd^2-] · H₂O Davar M. Boghaei ^1*, Fatemeh Behzadian-Asl ¹ and Hamid Reza Khavasi^{2 1} Department of Chemistry, Sharif University of Technology, P.O. Box 11155-9616, Tehran, Iran ² Department of Chemistry, Shahid Beheshti University, Evin, Tehran 1983963113, Iran Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.     

Synthesis,Crystal Structure and Characterization of (Z)-2-N′-hydroxyisonicotinamidine

The compound (Z)-2-N′-hydroxyisonicotinamidine, (2) was synthesized and characterized by ¹H NMR, FT-IR, FAB-Mass, UV-Visible Spectra, and elemental Analysis. Its molecular structure was solved by single crystal X-ray diffraction method. The title molecule, C₆H₇N₃O is crystallized in the orthorhombic crystal system with the space group Pna2₁ and with unit cell parameters a = 12.5664(8) Å, b = 8.8622(6) Å, c = 5.7953(4) Å, α = 90°, β = 90°, γ = 90°, and Z = 4. The molecular and crystal structure of the title molecule is stabilized by an intramolecular interaction of the type N—H···O, and the intermolecular interactions of types N—H···N and O—H···N.     

Synthesis and Crystal Structure of a Novel Macrocyclic Bisimidazolylidene Picrate Containing Two Silver(I) <Emphasis Type="Italic">N</Emphasis>-heterocyclic Carbene Units

Abstract  

A novel macrocyclic silver(I)-NHC complex was prepared by the quaternization reaction and anion metathesization reaction from 1-(1H-Imidazole-1-yl)methylene-1H-1,2,4-triazole as starting material. Its molecular structure was determined by single crystal X-ray diffraction and NMR spectroscopy, it crystallizes in triclinic space group P − 1 with a = 11.3286(10) ?, b = 11.4226(10) ?, c = 12.3987(12) ?, α = 79.0060(10)°, β = 82.1780(10)°, γ = 84.5930(10)°, V = 1556.5(2) ?³, z = 2. The silver ion was coordinated by the two carbene C atoms of two independent triazolylidene rings in linear geometry. A 20-membered macrometallacycle was formed through the bridged interaction between two silver ions and two carbene ligands. There are weak π–π interactions between two picrate anions or between picrate anion and triazolylidene ring.