Coordination dimers constructed from metal(II) halides and the organic ligand 1,2-dimethoxy- 4,5-bis(2-pyridylethynyl)benzene

A series of new coordination compounds has been synthesized using the organic ligand 1,2-dimethoxy-4,5-bis(2-pyridylethynyl)benzene (dmpeb). The compounds all form dimers consisting of two metal cations bridged by two ligand molecules. Charge balance is provided by halide ligands, and the four-coordinate metal centers are distorted from the ideal tetrahedral environment. [CoCl₂(dmpeb)]₂ (1) crystallizes in the monoclinic space group P2₁/n with a = 8.5272(6) Å, b = 18.3653(13) Å, c = 13.3493(9) Å, β = 103.574(2)^°, V = 2032.2(2) ų, Z = 2. [ZnCl₂(dmpeb)]₂ (2) is isostructural to 1 and has the cell parameters a = 8.5495(4) Å, b = 18.4049(8) Å, c = 13.3692(6) Å, β = 103.4460(10)^°, V = 2046.01(16) ų, Z = 2. [ZnBr₂(dmpeb)]₂ (3) is also isostructural to 1 with a = 8.7882(5) Å, b = 18.7260(12) Å, c = 13.3857(8) Å, β = 102.5990(10)^°, V = 2149.8(2) ų, Z = 2. Additionally, the compounds [ZnI₂(dmpeb)]₂ (4, cell parameters: a = 8.9650(5) Å, b = 19.1251(10) Å, c = 13.4160(7) Å, β = 101.1660(10)^°, V = 2256.7(2) ų, Z = 2), [HgCl₂(dmpeb)]₂ (5, cell parameters: a = 8.8457(7) Å, b = 18.4030(15) Å, c = 13.3711(11) Å, β = 104.246(2)^°, V = 2109.7(3) ų, Z = 2), and [HgBr₂(dmpeb)]₂ (6, cell parameters: a = 9.0576(5) Å, b = 18.8634(11) Å, c = 13.4535(8) Å, β = 102.9780(10)^°, V = 2239.9(2) ų, Z = 2) are also isostructural to 1. A seventh dimeric compound, [HgI₂(dmpeb)]₂, not isostructural to the others was also characterized by X-ray crystallography. [HgI₂(dmpeb)]₂ (7) crystallizes in the triclinic space group P-1 with a = 8.8028(5) Å, b = 12.0990(7) Å, c = 12.4082(7) Å, α = 109.7240(10)^°, β = 107.3680(10)^°, γ = 93.0880(10)^°, V = 1169.57(12) ų, Z = 1.     

Crystal structure analysis of 4-phenylquinolin-2-(1<Emphasis Type="Italic">H</Emphasis>)-one

The crystal structure of 4-phenylquinolin-2-(1H)-one (C₁₅H₁₁NO) is determined by X-ray diffraction. The compound crystallizes in the orthorhombic crystal system (space group Pbca) with the unit cell parameters a = 7.382(2) Å, b = 21.795(3) Å, c = 14.066(5) Å, and Z = 8. The structure is solved by direct methods and refined to an R-value of 0.0398 for 1360 observed reflections [F₀ > 4σ (F₀)]. The quinoline moiety and the substituted phenyl ring are nearly planar. The dihedral angle between these two moieties is 64.65(6)°. The crystal structure is stabilized by two intermolecular N-H?O and C-H?O interactions.     

Crystal structure and spectral characteristics of 2,4,7-trinitro-9-fluorenone

The crystal structure of 2,4,7-trinitro-9-fluorenone C₁₃H₅N₃O₇ is determined by X-ray diffraction analysis. The crystals are monoclinic, a = 4.024(1) Å, b = 16.763(3) Å, c = 18.250(4) Å, β = 96.32(3)°, V = 1223.6(5) ų, Z = 4, space group P2₁/c, and R = 0.0640 for 605 reflections with I > 2σ(I). The crystal is built of planar isolated molecules. The compound is characterized using IR and electronic absorption spectroscopy.     

X-ray mapping in heterocyclic design: XII. X-ray diffraction study of 2-pyridones containing cycloalkane fragments annelated to the C(5)-C(6) bond

The structures of 4,6-dimethyl-1H-pyridin-2-one [a = 6.125(2) Å, b = 15.153(4) Å, and c = 14.477(4) Å, Z = 8, space group Pbca], the 2: 1: 1 complex of 4-methyl-1,5,6,7-tetrahydro-2H-cyclopenta[b]pyridin-2-one with phosphoric acid and methanol [a = 11.181(2) Å, b = 14.059(6) Å, c = 13.593(4) Å, β = 97.78(2)°, Z = 8, space group P2₁/n], 4-methyl-1,5,6,7,8,9-hexahydro-2H-cyclohepta[b]pyridin-2-one [a = 12.565(6) Å, b = 5.836(6) Å, c = 13.007(3) Å, β = 93.10(3)°, Z = 4, space group P2₁/n], and 4-methyl-5,6,7,8,9,10-hexahydrocycloocta[b]pyridin-2(1H)-one [a = 12.955(3) Å, b = 6.1595(15) Å, c = 13.038(3) Å, β = 95.50(2)°, Z = 4, space group P2₁/n] are determined by single-crystal X-ray diffraction. The structures are solved by direct methods and refined by the full-matrix least-squares procedure in the anisotropic approximation to R = 0.0755, 0.0644, 0.0754, and 0.0569, respectively. The structures of 4-methyl-1,5,6,7-tetrahydro-2H-cyclopenta[b]pyridin-2-one [a = 7.353(4) Å, b = 8.176(4) Å, c = 13.00(1) Å, β = 105.64(2)°, Z = 4, space group P2₁/c] and 2-oxo-1,2,5,6,7,8-hexahydroquinoline-3-carbonitrile [a = 5.9870(2) Å, b = 16.5280(5) Å, c = 9.6540(3) Å, β = 111.52(4)°, Z = 4, space group P2₁/c] are studied by the powder diffraction technique. The structures are solved using the grid search procedure and refined by the Rietveld method to R _wp = 0.108 and 0.058, R_exp = 0.032 and 0.027, R _p = 0.076 and 0.043, R _b = 0.123 and 0.077, and χ² = 7.9 and 3.64, respectively. In all the structures, hydrogen bonds involving the N, H, and O atoms of the pyridone fragment are formed.     

X-ray crystallography of methyl (6-amino-5-cyano-2-methyl-4-(2-nitrophenyl)-4<Emphasis Type="Italic">H</Emphasis>-pyran)-3-carboxylate

The organic carbonitrile namely methyl (6-amino-5-cyano-2-methyl-4-(2-nitrophenyl)-4H-pyran)- 3-carboxylate is synthesized via one-pot multi-component reaction at room temperature using commercially available urea as inexpensive and environmentally benign organo-catalyst and its crystal structure is determined by X-ray technique. The crystals are monoclinic, sp. gr. C2/c, a = 12.3069(8) Å, b = 9.7023(7) Å, c = 24.812(2) Å, β = 94.862(6)°, Z = 8. The dihedral angle between pyran and phenyl rings is 87.8(1)°; the pyran ring is almost planar The dihedral angle between the mean planes of phenyl ring and nitro group is 44.4(2)°. The crystal structure is stabilized by N?H···N and N?H···O hydrogen bonds. In addition, C?H···π interactions are also observed in the crystal structure.     

X-ray structure analysis of 4-cyano-4′-<Emphasis Type="Italic">n</Emphasis>-undecyloxybiphenyl

The structure of a liquid crystal of 4-cyano-4′-n-undecyloxybiphenyl (C₂₄H₃₁NO) is determined by X-ray diffraction. The compound crystallizes in the monoclinic crystal system (space group C2/c) with the unit cell parameters a = 84.108(7) Å, b = 7.159(2) Å, c = 6.922(2) Å, and β = 91.6(4)°. The structure has been solved by direct methods and refined to the residual index R₁ = 0.067. Both phenyl rings are almost planar, and the dihedral angle between these rings is 31.5(6)°.     

Synthesis and structure of oxovanadium(IV) complexes [VO(<Emphasis Type="Italic">Acac</Emphasis>)<Subscript>2</Subscript>] and [VO(<Emphasis Type="Italic">Sal</Emphasis>: <Emphasis Type="Italic">L</Emphasis>-alanine)(H<Subscript>2</Subscript>O)]

Bis(acetylacetonato)oxovanadium C₁₀H₁₄O₅V (I) and (S)-[2-(N-salicylidene)aminopropionate]oxovanadium monohydrate C₁₀H₉NO₅V (II) are synthesized. The crystal structures of compounds I and II are determined using single-crystal X-ray diffraction. Crystals of compound I are triclinic, a = 7.4997(19) Å, b = 8.2015(15) Å, c = 11.339(3) Å, α = 91.37(2)°, β = 110.36(2)°, γ = 113.33(2)°, Z = 2, and space group \(P\bar 1\). Crystals of compound II are monoclinic, a = 8.5106(16) Å, b = 7.373(2) Å, c = 9.1941(16) Å, β = 101.88(1)°, Z = 2, and space group P2₁. The structures of compounds I and II are solved by direct methods and refined to R₁ = 0.0382 and 0.0386, respectively. The oxovanadium complexes synthesized are investigated by vibrational spectroscopy.     

Synthesis,Crystal Structure,and Free Radical Scavenging Activity of 4-Aminopyridinium 3,5-Dinitrobenzoate

The crystal structure of 4-aminopyridinium 3,5-dinitrobenzoate, C₁₂H₁₀O₆N₄, has been determined by single-crystal X-ray diffraction technique. The title compound crystallizes in the monoclinic sp. gr. P21/n with the unit cell parameters: a = 7.4726(3) Å, b = 23.0898(9) Å, c = 8.0744(4) Å, V = 1338.64(10) ų, Z = 4. The asymmetric unit of the compound consists of one 3,5-dinitrobenzoate anion and 4-aminopyridine cation. The adjacent anions and cations are linked through two N?H···O hydrogen bonds, N2?H2A···O5 and N₂?H2B···O6, to form an infinite chain of anions and cations, extended along the [010] direction.     

Structural study of new compound Bi<Subscript>2.53</Subscript>Li<Subscript>0.29</Subscript>Nb<Subscript>2</Subscript>O<Subscript>9</Subscript> by the powder neutron diffraction method

A new compound of composition Bi_2.53Li_0.29Nb₂O₉ was synthesized in the course of the search for new materials with high ionic conductivity. Its crystal structure was determined from the neutron diffraction data. The new compound Bi_2.53Li_0.29Nb₂O₉ is crystallized in the orthorhombic system, sp. gr. Cmc2₁, and unit-cell parameters a = 24.849(1) Å, b = 5.4536(3) Å, and c = 5.4619(2) Å at T = 290 K (a = 24.843(2) Å, b = 5.4456(5) Å, and c = 5.4546(5) Å at T = 10 K). Within the temperature range 10–870 K, no structural phase transitions were revealed. The atomic coordinates and the thermal factors in the isotropic approximation were refined by the Rietveld method at 290 and 10 K. The data obtained were analyzed based on the calculated local balance of bond strengths.     

Crystal and molecular structure of 2-[(4-nitrophenyl)carbonyl]cyclohex-1-ene-1-yl 4-nitrobenzoate

The crystal structure of 2-[(4-nitrophenyl)carbonyl]cyclohex-1-ene-1-yl 4-nitrobenzoate is studied (T = 173 K, R1 = 0.0354 for 2713 observed reflections). This crystal is orthorhombic, a = 7.8367(8) Å, b = 9.6082(10) Å, c = 23.856(3) Å, V = 1796.3(3) ų, space group P2₁2₁2₁, and Z = 4. The molecule has a folded configuration, which is stabilized by π-π interactions between its two parts. A system of intermolecular C-H...O hydrogen bonds (H...O, 2.44–2.67 Å; CHO angles 122°–169°) and intramolecular C-H...O contacts closing five-membered cycles (H...O, 2.42–2.59 Å; CHO angles 96°–102°) are formed in the structure.     

Synthesis,structural characterization,and DFT calculations of 3-buthyl-4-(3-methyl-3-mesitylcyclobut-1-yl)-1,3-thiazole-2(3<Emphasis Type="Italic">H</Emphasis>)-thione

The title compound, C₂₁H₂₉NS₂, has been synthesized and its crystal structure has been determined from single crystal X-ray diffraction data. Crystals are monoclinic, a = 11.4923(8), b = 13.1842(7), c = 14.6583(8) Å, β = 109.983(6)°, sp. gr. P2₁/c, Z = 4. Mesityl and thiazole groups are in cis positions with respect to the cyclobutane ring. The cyclobutane ring is puckered, with a dihedral angle of 26.6(2)° between the two three-atom planes. The crystal structure involves one weak intermolecular C–H···S hydrogen-bond. The molecular geometry was also optimized using density functional theory (DFT/B3LYP) method with the 6-311G(d, p) basis set in ground state. Geometric parameters (bond lengths, bond angles and torsion angles) and vibrational assignments have been calculated theoretically and compared with the experimental data.     

Synthesis and characterization of 9-(4-nitrophenyl)3,3,6,6-tetramethyl-3,4,6,7,9,10-hexahydro-1,8(2H,5H) acridinedione and its methoxyphenyl derivative

9-(4-Nitrophenyl)-3,3,6,6-tetramethyl-3,4,6,7,9,10-hexahydro-1,8(2H,5H) acridinedione (NTHA) crystallizes in orthorhombic space group P2₁2₁2₁ with a = 5.9716(1) Å, b = 18.0476(3) Å, c = 19.2445(2) Å, V = 2074.04(5) ų, Z = 4, D_cal = 1.263 Mg m^?3 and R = 0.0521 (wR = 0.1326) for 4078 observed reflections. 9-(4-Nitrophenyl)-10-(4-methoxyphenyl)-3,3,6,6-tetramethyl-3,4,6,7,9,10-hexahydro-1,8(2H,5H) acridinedione NMTHA, crystallizes in monoclinic space group P2₁/c with a = 15.669(5) Å, b = 10.652(4) Å, c = 18.337(6) Å, β = 108.25(1)^°, V = 2906.66(2) ų, Z = 4, D_cal = 1.245 Mg m^?3 and R = 0.0725 (wR = 0.1847) for 5105 observed reflections. The experimental values are compared with the theoretical values calculated based on the semiemperical methods. The structures are stabilized by N–H?sO and C–H?sO types of intermolecular interactions in addition to van der Waals forces.     

Synthesis and crystal structure of 2-acetylnaphthalen-6-yl 4-methylbenzosulfonate

The title compound has been synthesized by the reaction of 1-(6-hydroxy-2-naphthyl)-1-ethanone (2) with p-toluenesulfonyl chloride. Its structure was determined by single crystal X-ray diffraction. 2-Acetylnaphthalen-6-yl 4-methylbenzosulfonate (3) crystallizes in the orthorhombic space group Pbca with a = 12.727(3) Å, b = 14.560 (3) Å, c = 17.688 (4) Å, V = 3277.8 (11) ų, and Z = 8. The results demonstrate that the dihedral angle between the benzene ring and the naphthalene ring is 116.5^°, and the length (1.417 Å) of single C–O bond of 3 is longer than that of single C–O bond in the relative compounds.     

Crystal structure of the molecular complex of 3-[1-(4-nitrophenyl)-3-oxobutyl]-4-hydroxychromen-2-one with ethanol

The crystal structure of 2,3H-2-methyl-4-(4-nitrophenyl)-5-oxobenzopyrano[3,4-e]dihydropyran-2-ol is investigated using X-ray diffraction. The unit cell contains an ethanol molecule that forms hydrogen bonds with O-H and C-O groups of two molecules of the main compound and acts as a proton donor and a proton acceptor in these hydrogen bonds. Owing to these interactions, infinite chains are formed in the crystal. The crystallographic data for the structure of C₁₉H₁₅NO₆·C₂H₅OH (M = 399.39) are as follows: the crystals are triclinic, space group P1, a = 5.5340(3) Å, b = 8.0109(4) Å, c = 11.0112(5) Å, α = 88.773(2)°, β = 84.788(2)°, γ = 79.958(2)°, and Z = 1.     

Synthesis and structure of methyl 8-allyl-6-bromo-2-methyl-1,2,3,4-tetrahydroquinoline-4-carboxylate

The compound C₁₅H₁₈NO₂Br was synthesized and characterized by X-ray diffraction. The crystals belong to the monoclinic system, sp. gr. P2₁/n, a = 8.913(2) Å, b = 23.637(6) Å, c = 13.892(3) Å, β = 90.31(2)°, Z = 8, V = 2926.8(12) ų, ρ_calc = 1.472 g/cm³. The bond lengths and bond angles in two molecules are equal within an experimental error and are typical of this class of compounds. The conformational differences of the saturated heterocyclic and methoxycarbonyl fragments of the molecules result in the presence of two crystallographically independent molecules in the crystal structure.     

Crystal structure analysis of two terpene derivatives

The crystal structures of two terpene derivatives, 2,4,5,6,7,7a-hexahydro-7a-hydroxy-3,6-dimethyl-2-benzofuranone (compound I) and β-cyclolavandulic acid (compound II), were determined by single-crystal diffractometry. Compound I, C₁₀H₁₄O₃, crystallizes in the orthorhombic space group P2₁2₁2₁ with the unit cell parameters a = 6.715(1) Å, b = 7.043(1) Å, c = 20.292(3) Å, and Z = 4. The six-membered ring has an ideal chair conformation. The five-membered ring is planar. Compound II, C₁₀H₁₆O₂, crystallizes in the monoclinic space group P2₁/n with the unit cell parameters a = 8.446(1) Å, b = 12.156(1) Å, c = 9.901(1) Å, β = 106.29(1)°, and Z = 4. The cyclohexene ring exhibits a half-chair conformation. Both the crystal structures are stabilized by intermolecular O-H?O hydrogen bonds.     

X-ray mapping in heterocyclic design: XIV. Tricyclic heterocycles based on 2-Oxo-1,2,5,6,7,8-hexahydroquinoline-3-carbonitrile

The structures of four compounds are studied using single-crystal X-ray diffraction: 1-[2-(4-chlorophenyl)-2-oxoethyl]-2-oxo-1,2,5,6,7,8-hexahydroquinoline-3-carbonitrile [a = 4.908(4) Å, b = 11.644(10) Å, c = 13.587(2) Å, β = 94.31(5)°, Z = 2, space group P2₁]; 2-[2-(4-chlorophenyl)-2-oxoethoxy]-5,6,7,8-tetrahydroquinoline-3-carbonitrile [a = 7.6142(8) Å, b = 14.778(2) Å, c = 14.132(2) Å, β = 100.38(1)°, Z = 4, space group P2₁/c]; 4-(aminocarbonyl)-2-(chlorophenyl)-6,7,8,9-tetrahydro[1.3]oxazolo[3,2-a]quinolin-3-ium per-chlorate [a = 5.589(7) Å, b = 24.724(15) Å, c = 13.727(5) Å, β = 97.66(9)°, Z = 4, space group P2₁/n]; and (3-amino-5,6,7,8-tetrahydrofuro[2,3-b]quinolin-2-yl)-(4-chlorophenyl) methanone [a = 7.150(2) Å, b = 7.4288(10) Å, c = 15.314(3) Å, α = 98.030(10)°, β = 99.21(2)°, γ = 105.34(2)°, Z = 2, space group \(P\bar 1\)]. The structures are solved by direct methods and refined by the full-matrix least-squares procedure in the anisotropic approximation to R = 0.0728, 0.0439, 0.1228, and 0.0541, respectively. The structure of 1-(4-chlorophenyl)-4-piperidin-1-yl-8,9-dihydro-7H-pyrrolo[3.2.1-ij]quinoline-5-carboxamide [a = 23.9895(9) Å, b = 5.1557(3) Å, c = 17.0959(9) Å, β = 106.43°, Z = 4, space group P ₁/c] is investigated by X-ray powder diffraction. This structure is solved using the grid search procedure and refined by the Rietveld method to R _wp = 0.0773, R _exp = 0.0540, R _p = 0.0585, R _b = 0.1107, and χ ² = 1.78.     

X-ray mapping in heterocyclic design: XV. Tricyclic heterocycles based on 2-oxo-2,5,6,7-tetrahydro-1<Emphasis Type="Italic">H</Emphasis>-cyclopenta[<Emphasis Type="Italic">b</Emphasis>]pyridine-3-carbonitrile

The structures of five compounds are studied using single-crystal X-ray diffraction: 2-oxo-2,5,6,7-tetrahydro-1H-cyclopenta[b]pyridine-3-carbonitrile [a = 15.641(8) Å, b = 9.373(5) Å, c = 7.387(4) Å, β = 92.91(5)°, Z = 4, space group P2₁/c]; 1-[2-(4-chlorophenyl)-2-oxoethyl]-2-oxo-2,5,6,7-tetrahydro-1H-cyclopenta[b]pyridine-3-carbonitrile [a = 4.728(4) Å, b = 28.035(11) Å, c = 11.184(3) Å, Z = 4, space group P2₁2₁2₁]; 2-[2-(4-chlorophenyl)-2-oxoethoxy]-6,7-dihydro-5H-cyclopenta[b]pyridine-3-carbonitrile [a = 10.1202(13) Å, b = 11.2484(18) Å, c = 13.4323(19) Å, β = 102.05(1)°, Z = 4, space group P2₁/c]; 2-(4-chlorophenyl)-3a, 6,7,8-tetrahydrocyclopenta[e][1.3]oxazolo[3.2-a]pyridine-4-carboxamide perchlorate [a = 7.702(2) Å, b = 9.599(3) Å, c = 23.798(5) Å, β = 93.44(2)°, Z = 4, space group P2₁/c]; and (3-amino-6,7-dihydro-5H-cyclopenta[b]furo[3.2-e]pyridin-2-yl)(4-chlorophenyl)methanone [a = 7.3273(2) Å, b = 13.390(3) Å, c = 28.792(8) Å, Z = 8, space group Pbca]. The structures are solved using direct methods and refined by the full-matrix least-squares procedure in the anisotropic approximation to R = 0.0580, 0.0724, 0.0469, 0.0477, and 0.0418, respectively.     

Synthesis and crystal structure of the [Co<Subscript>2</Subscript>(Nicotinamide)<Subscript>4</Subscript>(C<Subscript>4</Subscript>H<Subscript>9</Subscript>COO)<Subscript>4</Subscript>(H<Subscript>2</Subscript>O)] complex

The [Co₂ L ₄(C₄H₉COO)₄(H₂O)] coordination compound of cobalt(II) valerate with nicotinamide (L) is synthesized and studied by IR spectroscopy. The crystal structure of the synthesized compound is determined. The crystals are triclinic, and the unit cell parameters are as follows: a = 10.2759(10) Å, b = 16.3858(10) Å, c = 16.4262(10) Å, α = 100.538(10)°, β = 101.199(10)°, γ = 90.813 (10)°, Z = 2, and space group P \(\bar 1\). The structural units of the crystal are dimeric molecular complexes in which pairs of cobalt atoms are linked by triple bridges formed by oxygen atoms of two bidentately coordinated valerate anions and a water molecule. The octahedral coordination of each cobalt atom is complemented by the pyridine nitrogen atoms of two nicotinamide ligands and the oxygen atom of the monodentate valerate group. The hydrocarbon chains of the valerate anions are disordered over two or three positions each.     

Crystal structure of <Emphasis Type="Italic">p</Emphasis>-carboxyphenylhydrazone benzoylacetone

The crystal structure of p-carboxyphenylhydrazone benzoylacetone is determined. The crystals are monoclinic, a = 13.614(4) Å, b = 11.388(2) Å, c = 20.029(6) Å, β = 104.82(2)°, V = 2339(9) ų, Z = 8, space group C2/c, and R = 0.038 for 1622 reflections with I > 2σ(I). The crystal is built of C₁₇H₁₄N₂O₄ neutral molecules that are linked by O-H?O hydrogen bonds between the carboxyl groups into centrosymmetric pseudodimers. The effect of carboxylation of the phenylhydrazone fragment and the position of the carboxyl group on the molecular packing in the crystal is determined. The N(1)-H(1N)?O(1) intramolecular hydrogen bond (N-H, 0.94 Å; H?O, 1.87 Å; N?O, 2.59 Å; and the N-H?O angle, 133°) is formed in the molecule.