Two-dimensional crown ether complex. Synthesis and crystal structure of [Na(N15C5)]<Subscript>2</Subscript>[Cu(mnt)<Subscript>2</Subscript>]

A novel crown ether complex [Na(N15C5)]₂[Cu(mnt)₂] (1) (where N15C5 = 2,3-naphtho-15-crown-5 and mnt = maleonitriledithiolate, [C₂S₂(CN)₂]^2–) was synthesized and characterized by elemental analysis, FT-IR spectra, UV-visible spectra and single crystal X-ray diffraction. Structural analysis reveals that the complex 1 consists of two [Na(N15C5)]⁺ complex cations and one [Cu(mnt)₂]^2– complex anion and the complex molecules are assembled into a novel 2D network by Na–N interactions. In the network, there are 34-member macrocycles formed by four sodium ions of complex cations and four complex anions through Na–N bonds. In each macrocycle, – stacking interactions occurred between two parallel naphthylene moieties of N15C5. It is interesting that the 2D network displays an open-capped wave-like sheet viewed along the crystallographic a axis.     

C(4) helices,Br⋅<Emphasis Type="Italic">s</Emphasis>Br interaction and <Emphasis Type="Italic">R</Emphasis><Stack><Subscript>4</Subscript><Superscript>2</Superscript></Stack> (10) ring in bromoipriflavone

The title compound, 8-bromo-7-isopropoxyisoflavone (bromoipriflavone), C₁₈H₁₅O₃Br, crystallizes in tetragonal crystal system, space group I4₁/a with cell constants a = 21.396(2) Å, c = 13.588(2) Å, V = 6220.2(14) ų and Z = 16. Bromoipriflavone is composed of a benzopyranone moiety, a phenyl moiety, an isopropoxy group and a bromine atom. The benzopyranone ring is not coplanar with the phenyl ring with a dihedral angle of 55.1. The molecules are stacked into a C(4) helices down [001] via – stacking and hydrogen bonds, the C(4) helices are assembled into three-dimensional network via strong BrsBr interactions and synthons R₄²(10) formed by two tri-centered C–HsO hydrogen bonds, resulting in a distinctive high-symmetry supramolecule. The title compound was also characterized by IR and ¹H NMR.     

Synthesis,thermal reactivity and structure of 1,2-bis(4-hydroxy-3-methoxyphenylethynyl)benzene

The crystal structure of the new enediyne 3 was determined by X-ray diffraction. 3 crystallizes in the orthorhombic space group Pbca (No. 61) with a = 12.7148(9) Å, b = 7.4872(8) Å, c = 38.890(4) Å, = = = 90 and Z = 8. The three-dimensional structure is characterized by an 8-membered cyclic array linking four molecules of 3 by hydrogen bonding between phenolic and methoxy groups. Furthermore, stabilization by –-stacking and CH s interactions is present. The important cd distance (between the two terminal acetylene carbons of the enediyne) which is relevant for the Bergman cyclization, was determined to 401 pm, being in good agreement with the high cyclization barrier ( G = 147.9 kJ mol^–1 at 220C) that was determined by differential scanning calorimetry (DSC).     

Supramolecular structure of tetrakis-μ-(4-chloro-3-nitrobenzoato)-bis(methanol)dicopper(II)

The title compound, [Cu₂(II)(4-Cl-3-NO₂–C₆H₃CO₂)₄(CH₃OH)₂] or [Cu₂(4-chloro-3-nitrobenzoate)₄(MeOH)₂] has been prepared and its structure determined using X-ray crystallography. The complex crystallizes in the triclinic space group P-1 with a = 9.6887(9)Å, b = 10.6448(9)Å, c = 11.4194(10)Å, = 108.094(2), = 110.682(2), = 105.055(2), V = 952.691(15)ų, and Z = 1. The structure consists of centrosymmetric dimers in which the Cu(II) atoms display a square pyramidal CuO₅ coordination, with four carboxylate O atoms in the basal plane [CuO 1.951(2)–1.968(2)Å] and the methanol O atoms in the apical position [CuO 2.170(2)Å]. The Cu atoms are 2.614(1)Å apart and are bridged by four benzoate groups. The discrete dimers are extended into 1D chains that result from hydrogen bonding between the coordinated methanol on one Cu(II) dimer and the nitro substituent on an adjacent Cu(II) dimer. The chains are interdigited and held by – stacking interactions forming 3D supramolecular array.     

Self-assemblies of Ni(II) with phenanthroline and maleate anions: [Ni(H2O)3(phen)L] ⋅ H2O (1) and [Ni(H2O)2(phen)L] ⋅ 2H2O (2) with H2L = maleic acid

The complex [Ni(H₂O)₃(phen)(C₄H₂O₄)] H₂O (1), which was obtained by reaction of phenanthroline, Ni(NO₃)₂ 6H₂O, and maleic acid in CH₃OH/H₂O at pH = 7.05, crystallized in the monoclinic space group P2₁ (no. 4) with cell dimensions: a = 9.350(1) Å, b = 7.631(1) Å, c = 12.821(1) Å, = 106.25(1), and D _calc = 1.607 g/cm³ for Z = 2. The Ni atoms are each octahe drally coordinated by one chelating phen ligand, three H₂O molecules and one monodentate maleato ligand to form [Ni(H₂O)₃(phen)(C₄H₂O₄)] complex molecules with d(Ni–O) = 2.038–2.090 Å, d(Ni–N) = 2.066, 2.089 Å. The formed complex molecules are, via the intermolecular hydrogen bonds, assembled into columnar 1D chains. Interdigitation of the chelating phen ligands of the neighboring chains leads to 2D layers and the crystal H₂O molecules are hydrogen bonded to the oxygen atoms of the maleate not coordinated to the Ni atom. However, reaction of NiCO₃, phen, and maleic acid in CH₃OH/H₂O at pH = 6.33 afforded [Ni(H₂O)₂(phen)(C₄H₂O₄)] 2H₂O (2), which crystallized in the triclinic space group (no. 2) with cell dimensions: a = 7.971(1) Å, b = 8.237(1) Å, c = 13.304(1) Å, = 81.005(6)°, = 87.877(8)°, = 78.322(8)°, and D _calc = 1.671 g/cm³ for Z = 2. The Ni atoms are each octahedrally coordinated by two N atoms of one phen ligand and four O atoms of two H₂O molecules and two bis–monodentate maleato ligands with d(Ni–O) = 2.041–2.120 Å and d(Ni–N) = 2.095 Å. The Ni atoms are bridged by the maleato ligands to generate 1D ¹ [Ni(H₂O)₂(phen)(C₄H₂O₄)_2/2] chains along [100]. The supramolecular assemblies of the 1D chains via – stacking inter- actions result in thick 2D layers parallel to (001), between which the noncoordinating H₂O molecules are sandwiched. The paramagnetic [Ni(H₂O)₂(phen)(C₄H₂O₄)_2/2] 2H₂O (2) obeys the Curie–Weiss law _m(T-) = 1.139cm³ mol^–1 K with the Weiss constant = –0.95 K.     

Crystal structure of 2-amino-3-methylpyridinium ortho-phthalate

A new crystal of 2-amino-3-methylpyridinium ortho-phthalate has been prepared and characterized by X-ray crystallography. The salt crystallizes in the monoclinic space group P2₁/c with a = 11.015(2) Å, b = 11.057(2) Å, c = 15.767(2) Å, = 90.00°, = 96.220(10)°, = 90.00°, V = 1909.0(5) ų, Z = 4. In the cell unit, the phthalate anion is linked with two pyridinium cations by NHO hydrogen bond on both sites of annular and exocyclic nitrogen atoms. The two pyridinium cations are arranged in a face-to-face pattern with a dihedral angle of 7.3° and a shortest aspectant distance of 3.4(1) Å between them, indicating the existence of – interaction. The C(5) atom is an electron donating center. The exocyclic N atom is an electron receiving center, which is consistent with features of imino resonance evidenced by bond lengths and angles. In the cell unit, two entities of pyridinium cation are aligned with each other in a face-to-face manner of electron receiving to donating center.     

Synthesis and crystal structure of [CuL0.5(Ac)2] n ⋅0.5nCHCl3 (L = 2,5-bis(4-pyridyl)-1,3,4-oxadiazole)

A one-dimensional complex [CuL _0.5(Ac)₂] _n 0.5nCHCl₃ (L being 2,5-bis(4-pyridyl)- 1,3,4-oxadiazole) has been synthesized and structurally characterized by X-ray diffraction: Monoclinic, space group C2/c with a = 27.217(3) Å, b = 13.0383(11) Å, c = 8.5671(9) Å, = 103.215(3)°, V = 2959.6(5) ų, Z = 8. The crystal structure of the complex reveals that the familiar lantern-type structure that is characteristic of dimetal tetracarboxylates of Cu^II ions, and the binuclear units were bridged by the angular ligands to form a one-dimensional zigzag chain coordination polymer. Every metal center is present in a distorted square-pyramidal coordination environment, consisting of coordination with one N atom of the ligand in the axial position and four O atoms of CH₃COO^– anions in equatorial positions. The Cu^IICu^II distance is 2.6060(9) Å. The title complex resides in the formation of a 3D network through – stacking interactions.     

Synthesis, crystal structure, and thermal analyses of triaqua-(1,10-phenanthroline-N,N′) succinatomanganese(II) dihydrate, [Mn(H2O)3(phen)(C4H4O4)]·2H2O

[Mn(H₂O)₃(phen)(C₄H₄O₄)]·2H₂O was obtained by reaction of freshly prepared MnCO₃, phen and succinic acid in CH₃OH/H₂O (1:1 v/v), and its crystal structure has been determined by single crystal X-ray diffraction methods. The title mixed ligand complex crystallizes in the triclinic space group with cell dimensions a = 7.590(1) Å, b = 9.324(1) Å, c = 13.917(1) Å, = 85.64(1)°, = 74.56(1)°, = 77.10(1)°, and D _calc = 1.584 g/cm³ for Z = 2. The crystal structure consists of the [Mn(H₂O)₃(phen)(C₄H₄O₄)] complex molecules and lattice H₂O molecules. The Mn atoms are each octahedrally coordinated by two N atoms of one phen ligand and four O atoms of three H₂O molecules and one succinato ligand with d(Mn—N) = 2.271 and 2.299 Å, and d(Mn—O) = 2.133–2.239 Å. Through intermolecular hydrogen bondings, the complex molecules are interlinked to form 2D layers, which are assembled by – stacking interactions into 3D framework with tunnels occupied by the lattice H₂O molecules. Thermal analyses showed that the title compound decomposes in two steps over the range 25–600°C upon heating in flowing Ar.     

Crystal structure of bis(2,3,5-trimethylpyridine N-oxide) 2,4,6-trinitrophenolate: Cation complex tied by the extremely strong OHO hydrogen bonding

The salt of bis(2,3,5-trimethylpyridine N-oxide) 2,4,6-trinitrophenolate, C₂₂H₂₅N₅O₉, crystallizes in monoclinic space group C2/c with a=12.411(2)Å, b=15.326(3)Å, c=13.559(3)Å, =113.13(1)°, V=2371.8(8)ų, Z=4, D _c=1.410 mg/m³, F(000)=1056. The molecule of 2,3,5-trimethylpyridine N-oxide is protonated. Two pyridine N-oxide molecules are linked by extremely strong OHO hydrogen bonding (2.378(4)Å) to form a cation complex. CHO hydrogen bonding and – interactions also play important role in stablizing the structure of the salt.     

The crystal structure of tris(4-methylpyridine) tricarbonylmolybdenum(0)

The title compound, Mo(4-CH₃C₅H₄N)₃(CO)₃, is monoclinic, P2₁/c, with cell dimensionsa=10.385(1),b=13.572(2),c=15.522(2) Å, =105.08(1)°,Z=4. The complex isfac-octahedral with approximate three-fold symmetry. The Mo–C bond lengths are 1.901–1.904(7) Å, distinctly shorter than in the parent Mo(CO)₆, and the Mo–N bond lengths are 2.297–2.331(5) Å.     

Crystal structure of 4-methylpyridinium 2,4-dinitrophenolate

A crystalline salt of 4-methylpyridinium 2,4-dinitrophenolate has been prepared and characterized by X-ray crystallography. The salt crystallizes in the monoclinic space group P2_1/c with a = 9.105(2), b = 7.617(2), c = 18.424(3) Å, = 90.00, = 101.19(1), = 90.00°, V = 1253.5(5) ų, and Z = 4. In the title salt, the phenolate and pyridinium ion are held by bifurcated hydrogen bonds of N–H···O, and are arranged in an almost coplanar manner to each other due to two sets of CHO hydrogen bonds. The geometrical arrangement in the title salt is characterized by the formation of herringbone motif of 4-methylpyridinium 2,4-dinitrophenolate. The herringbone motif is stablized by CHO hydrogen bonds. The face-to-face interval between the phenolate and pyridinium ring is 3.3094 Å, in a range governed by – interaction.     

Copper(I) nitrate π-complexation: Synthesis and crystal structure of [(CH2=CH−CH2)2NH2][Cu(NO3)2] compound

By means of alternating current electrochemical synthesis, triclinic crystals of [(C₃H₅)₂NH₂][Cu(NO₃)₂] -complex were obtained: space group ,a=7.218(2),b=7.536(2),c=10.231 (3) Å, =74.75(3), =82.47(3), .=77.22(3)°, andD _meas=1.80(1)g cm^–3 forZ=2. The structure consists of diallylammonium cations which form two -coordinate bonds to the same copper atom. Oxygen atoms from NO₃-anions complete the trigonal pyramidal metal environment. The coordinated C=C bonds are lengthened to 1.349(5) and 1.369(5) Å.     

X-ray crystal structure of the 1:1 dimethylpicric acid–acenaphthene complex

The dimethylpicric acid–acenaphthene complex is orthorhombic, space group P2₁2₁2₁; at 24° a = 7.3685(1), b = 15.4159(1), c = 16.1296(3) Å, D _x = 1.491(2) g cm^–3, V = 1832.19(4) ų, Z = 4. The phenolic OH group in the dimethylpicric acid is intramolecularly hydrogen bonded to one of the ortho nitro groups with an OO distance of 2.500(2) Å. This nitro group is twisted out of the plane of the benzene ring by 8.2°; the twist angles of the other nitro groups are 52.6 and 83.5°. The acenaphthene molecule deviates slightly from planarity as a consequence of the torsion angle at CH ₂-CH ₂ being 1.8 rather then 0°. The molecules pack in stacks of alternating picric acid and acenaphthene molecules. Each stack is surrounded by a close-packed arrangement of six other stacks. The acenaphthene molecules are 2.7° away from being parallel to the benzene ring in the picric acid. The distances from the benzene ring to the acenaphthene carbon atoms range from 3.26 to 3.49 Å on one side of the ring and from 3.30 to 3.54 Å on the other.     

Crystal structures of a series of 3,8-di[-2-aryl-1-azenyl]-1,3,6,8-tetraazabicyclo[4.4.1]undecanes

The crystal and molecular structure of a series of 3,8-di[-2-aryl-1-azenyl]-1,3,6,8-tetraazabicyclo[4.4.1]undecanes (1–5) have been determined by single crystal X-ray diffraction analysis. In all five compounds, the tetraazabicycloundecane portion of the molecule assumes a cage-like, folded structure with the aryltriazene moieties aligned approximately parallel; the structure is held in the folded configuration by either intramolecular or intermolecular – stacking forces. Crystal data: 1 C₁₉H₂₂N₁₀O₄, monoclinic space group P2₁/c, a = 10.1846(7), b = 9.9556(7), c = 20.819(2) Å, = 98.725(1)°, V = 2086.5 (3) ų, Z = 4; 2 C₂₃H₂₈N₈O₄, triclinic, space group P, a = 6.7064(7), b = 12.9662(14), c = 14.054(2) Å, = 94.796(2), = 91.621(2), = 104.836(2)°, V = 1175.7(2) ų, Z = 2; 3 C₁₉H₂₂N₁₀O₄, monoclinic, space group P2₁/c, a = 14.237(2), b = 13.520(2), c = 11.5805(12) Å, = 113.514(2)°, V = 2044.0(4) ų, Z = 4; 4 C₂₁H₂₂N₁₀, monoclinic, space group C2/c, a = 54.247(3), b = 11.5531(7), c = 12.9670(7) Å, = 95.710(1)°, V = 8086.4(8) ų, Z = 16; 5 C₂₅H₃₂N₈ 0₄, monoclinic, space group P2₁/c, a = 10.2908(7), b = 16.5687(12), c = 15.1662(10) Å, = 94,188(1)°, V = 2579.0(3) ų, Z = 4.     

Crystal structure of diethoxynitrobenzene-p-tert-butylcalix [4]arene⋅2(CH3)2C=O: Evidence of intra- and intermolecular CH/π interactions forced by crystal packing

Diethoxynitrobenzene-p-tert-butylcalix[4]arene2(CH₃)₂C=O crystallized in the monoclinic system, space group P2₁/c, with cell dimensions a = 16.1437(2) Å, b = 21.0292(2) Å, c = 18.9685(3) Å and = 110.308(1)°. The asymmetric unit consists of a diethoxynitrobenzene-p-tert-butylcalix[4]arene molecule and two solvated acetone molecules. Besides the usual CH/ interaction between p-tert-butylcalix[4]arene cavity and a solvated acetone, this structure shows the intra- and intermolecular CH/ interactions among a nitrobenzene ring, ethylene bridge of the ethoxynitrobenzene side chain and a solvated acetone molecule.     

Crystal structure of chloro(dicarbonyl) bis(acetonitrile) (π-2-methallyl) molybdenum(II)

The title compound crystallizes in the monoclinic spacegroup P2₁/m with a = 6.796(9), b = 12.145(14), c = 7.749(8)Å, = 101.86(1)°, and Z = 2. The crystal structure consists of molecules of [MoCl(CO)₂(NCMe)₂(³-C₃H₄Me-2)] with crystallographically imposed C_s symmetry and has a pseudo-octahedral geometry, with the -allyl group trans- to the chloro group and the two cis-carbonyl and acetonitrile groups occupying the equatorial plane.     

Tricarbonyl (η6 arene) chromium(0) complex derived from 8-phenylmenthol chiral auxiliary

(—)-8-Phenylmenthol was prepared and converted to the corresponding tricarbonyl (⁶-arene) chromium(0) complex. Derivitization as the acrylate ester (1) and subsequent X-ray analysis revealed a 1:1 mix of s-cis and s-trans acrylate in the unit cell, and geometric proximity to support a through-space stacking interaction in the case of the s-trans isomer. The dihedral angle between the best planes through the chromium-bound aryl ring and the acrylate group is 19.9° for the s-trans isomer and 34.4° for the s-cis isomer. Crystal data for (1): C₂₂H₂₆O₅Cr, monoclinic, P2₁ (No. 4), a = 10.269(1), b = 10.482(1), c = 19.787(2), = 95.85(1), Z = 4, and D _calc = 1.32 g cm^–3.     

Synthesis and X-ray structure of p-tolyl phenylthioglyoxylate

The title compound (C₁₅H₁₂O₂S) is triclinic witha=7.077(10),b=8.825(2),c=11.068(2) Å, =106.66(3)^o, Z=2, and space group P. The significant structural features lies in the two carbonyl groups of the thioglyoxylate which are oriented antiperiplanar to each other [–168.2(2)^o]. The central C(8)–C(9) bond is 1.553(3) Å. The phenyl rings are twisted with respect to the carbonyl groups. Short contacts are present between S and O(1) [2.652(2) Å] and also between S and O(2) [2.758(2) Å].     

Bis[aqua(2,5-bis(4-pyridyl)-1,3,4-oxadiazole)thiocyanate] cadmium(II): A three-dimensional framework built from hydrogen bonds and π-π stacking interactions

A three-dimensional (3D) network complex [Cd(L)₂(NCS)₂(H₂O)₂], L being 2,5-bis(4-pyridyl)-1,3,4-oxadiazole, has been synthesized and structurally determined by X-ray diffraction analysis: triclinic, space group P-1 with a = 7.8863(9) Å, b = 8.6287(10) Å, c = 11.4696(12) Å, = 94.346(2)°, = 109.331(2)°, = 94.354(2)°, Mr = 713.04, V = 730.13(14) ų, Z = 1. The crystal structure of the title complex reveals that it is a neutral molecule and the Cd(II) ion is at the center of symmetry. Each Cd(II) is six-coordinated and the CdN₄O₂ coordination sphere can be considered as an octahedron. The most striking feature of this complex resides in the formation of a 3D network through hydrogen bonds and - stacking interactions.     

Six-coordinated zinc complexes: [Zn(H2O)4(phen)] (NO3)2·H2O and [ZnNO3(H2O)(bipy)(Him)]NO3 (phen = 1,10-phenanthroline, bipy = 2,2′-bipyridine, and Him = imidazole)

Two novel six-coordinated zinc complexes, tetra-aqua(1,10-phenanthroline)zinc dinitrate monohydrate, [Zn(H₂O)₄(phen)](NO₃)₂·H₂O (1) and aqua(2,2-bipyridine)(imidazole)-nitratozinc nitrate, [ZnNO₃(H₂O)(bipy)(Him)]NO₃ (2) were prepared. Compound 1 crystallizes in the monoclinic space group P2₁/c with a = 8.780(4), b = 13.609(4), c = 15.368(5) Å, = 93.86(2)°C, V = 1832.1(12) ų. In 1, a phenanthroline molecule chelates the zinc atom and four water molecules complete the octahedral geometry around the metal. Compound 2 crystallizes in the monoclinic space group P2₁/n with a = 7.250(1), b = 24.554(4), c = 10.258(2) Å, = 107.880(10)°, V = 1737.9(5) ų. In 2, a bipyridine molecule and a nitrate anion chelate the zinc atom. An imidazole molecule and a water molecule then complete the six-coordinated geometry around zinc. The intermolecular packing is controlled by hydrogen bonding, especially in 1 and by stacking. The thermal stability of the compounds and the loss of water molecules and ligands was monitored by a thermogravimetric study.