Molecular structure of N-(2-phenylethyl)amide of α-(1,1-ethylenedioxy)-ethyl γ-hydroxybutyric acid (I) and1H NMR spectra of (I) and N-(p-methoxybenzyl)derivative (III)

The spectroscopic and X-ray investigation of the N-(2-phenylethyl) amide of -(1,1-ethylenedioxy)-ethyl--hydroxybutyric acid are reported. The¹H NMR spectra for the title structure and for the N-(p-methoxybenzyl) amide of -(1,1-ethylenedioxy)-ethyl--hydroxybutyric acid are given. The N-(2-phenylethyl)amide of -(1,1-ethylenedioxy)-ethyl--hydroxybutyric acid, C₁₆H₂₃O₄N, crustallizes in the monoclinic space groupP2 ₁/c witha=21.547(5),b=6.333(2),c=11.822(3) Å and =101.01(2)°. The dioxolane ring has a half-chair conformation with C₂(O3)=2.4° and ||_av=18.2°. The inconsiderable deviations from planarity of the six atoms of the amide group are caused mainly by twist around the C4–N1 bond and out-of-plane bending at the N1 atom ((C4–N1)=4°, X_N =7°, X_c =0.4° ). The amide group plane is nearly coplanar with the phenyl ring. The molecules are connected by two intermolecular hydrogen bonds.     

Pseudoacids. III: formation and structures of new cyclic oxocarboxylic acids

Crystal and molecular structures for aryl- and benzyl-substituted 3-hydroxy-3,4-dihydroisobenzopyran-1-one are described. For the 4,4-dimethyl derivative, two monoclinic modifications are produced on sublimation: (1) P2₁/c, a = 23.668(6) Å b = 11.749(4) Å c = 7.215(2) Å = 96.70(2); V = 1992.6(10) ų; (2) P2₁/c, a = 11.509(4) Å, b = 12.429(4) Å, c = 6.933(2) Å, = 91.12(3), V = 991.6(6) Å. In both, hydroxy groups are pseudoaxial, and molecules form dimeric complementary but noncooperative hydrogen bonds. In the 6-methoxy derivative (3), P2₁/c; a = 14.185(7) Å b = 4.105(4) Å c = 15.598(13) Å = 98.59(6); V = 898.1(10) ų, the hydroxy group is pseudoequatorial, and the intermolecular hydrogen bonding forms infinite chains. In the 4,4-dimethyl-7-nitro derivative (4), C2/c, a = 19.365(4), b = 8.425(2), c = 13.464(4), = 92.62(2), V = 2194.2(7) ų, the hydroxy group is pseudoaxial, and the intermolecular hydrogen bonding forms chains. Compared to the unmethylated compounds, the interbond angles within the ring at the dimethylated carbon are contracted.     

Conformations of highly hindered aryl ethers XXVI. Structural analysis by X-ray diffraction of 2,4-dinitronaphthyl-2′,6′-dimethylphenyl ether

The crystal structure of 2,4-dinitronaphthyl-2,6-dimethylphenyl ether, C₁₈H₁₄N₂O₅, has been determined by three-dimensional x-ray methods, as part of a study of hindered aryl ethers. The crystals are monoclinic, space groupP2₁/c witha = 13.416(1),b = 8.479(1),c = 14.808(2) Å, = 111.65(1) ° andZ = 4. The structure was solved by direct methods using program REL and was refined by full-matrix least squares to anR value of 0.050. The torsion angles that describe the diphenyl ether conformation are 60/22 ° for C2-C1-O1-C1/C1-O1-C1-C2, respectively. The average torsion angles for other naphthalene phenyl ethers are 65/25 °. There are no hydrogen bonds in this structure.Part XXV, Ciurlizza, G., Lehmann F, P. A., and Aguilar, J. A. (1973).Rev. Soc. Quim. Mex. 17, 74.     

Ortho-metalation and carboxylate coordination in the reaction between the dipotassium salt of phthalic acid and Cp*Ir(PMe3)Cl2: X-ray diffraction structure of Cp*Ir(PMe3)[C6H3(CO2)(CO2H)]

The cyclopentadienyl complex Cp*Ir(PMe₃)Cl₂ reacts with the dipotassium salt of phthalic acid in the presence of AgPF₆ via chloride substitution to give the ortho-metalated compound Cp*Ir(PMe₃)[C₆H₃(CO₂)(CO₂H)]. This new compound has been isolated by recrystallization and has been characterized in solution by ¹H and ¹³C NMR spectroscopies, and the solid-state structure has been verified by X-ray crystallography. Cp*Ir(PMe₃)[C₆H₃(CO₂)(CO₂H)] crystallizes in the monoclinic space group P2₁/c, a = 9.1010(6) Å, b = 16.715(1) Å, c = 14.3965(9) Å, = 108.24(1)°, V = 2080.0(2) ų, Z = 4, and d _calc = 1.813 mg/m³; R = 0.0276, R _w = 0.0810 for 2730 reflections with I > 2(I). Coordination of the benzene ring to the iridium center via one of the carboxylate groups and ortho-metalation of the C–H moiety that was to the iridium-bound carboxylate group is confirmed.     

Molecular structure of [(<Superscript>t</Superscript>Bu)<Subscript>2</Subscript>Al(μ-OC<Subscript>6</Subscript>H<Subscript>4</Subscript>-2-Me)]<Subscript>2</Subscript>

The molecular structure of [(^tBu)₂Al(-OC₆H₅-2-Me)]₂ has been determined. Both the ortho-tolyl methyl groups are oriented towards Al(2). The intramolecular steric interaction between the ortho-methyl groups and the tert-butyl ligands results in the geometry about the bridging oxygen being significantly distorted while the geometries about the aluminum centers show a distortion from tetrahedral that is less than the sterically less hindered [(^tBu)₂Al(-OPh)]₂. Crystal data: group C2/c, a = 13.733(3) Å, b = 15.135(3) Å, c = 15.420(3) Å, = 104.24(3), V = 3106(1) ų, Z = 4, R = 0. 0612, wR₂ = 0.1787.     

Crystal and molecular structure ofo-chlorobenzylidenemalononitrile

The crystal structure ofo-chlorobenzylidenemalononitrile, C₁₀H₅ClN₂, has been determined by X-ray crystallographic analysis. The compound crystallizes in the monoclinic space groupP2₁/c, with unit cell dimensionsa = 3·971,b = 21·140,c = 10·747 Å, = 95·29 °;Z = 4. The structure was solved by matching an assumed molecular shape to the near-origin peaks of a sharpened vector map, the detail being established by Fourier syntheses. Refinement by full-matrix least squares converged to an indexR of 0·097 for 1729 reflections from CuK Weissenberg photographs.The molecular components, the phenyl and malononitrile groups, are individually planar but mutually tilted with a dihedral angle of 12·7 °. The deviation from planarity is related to steric hindrance between the malononitrile group and theortho-hydrogen of the phenyl ring.     

Crystal structure and luminescence of 2,7-dimethylnaphthalene-1-carbonitrile

The title compound crystallizes in the monoclinic space group P2 ₁/c: M _r = 181.2; a = 7.119(1), b = 18.389(4), c = 7.5385(6) Å = 91.661(7)° V = 986.4(5) ų; and Z = 4. The purified material shows fluorescence similar to other naphthalene derivatives: monomer fluorescence (_max 350-370 nm) in the solid state and in dilute solutions, and excimer fluorescence (_max 421 nm) in concentrated solutions. Intense blue-green luminescence (_max 490 nm) is observed in some partially purified crystalline samples. This is attributed to phosphorescence from two isomeric bromodimethylnaphthalenecarbonitrile impurities detected by GC-MS analysis.     

Crystal structure and spectroscopic study of methyl (Z)-6-anilino-4-cyano-2,3-dimethoxy-6-azapentafulvene-1-carboxylate

The molecular and crystal structures of the title compound have been determined. The crystals are monoclinic: C2/c (15),a=21.787(7),b=7.025(6),c=20.165(8) Å,=96.03(2)°,V _c =3069 ų,Z=8,D _x=1.36 mg m^–3, =(Mo K)=0.71069 Å. The structure was solved by direct methods and refined with 1484 reflections to a finalR value of 0.057. Mass and spectral data (ir, uv,¹H and¹³C nmr) are also reported. The structure appears to be polyolefinic having two independent push-pull systems on the fulvenic ring.     

Crystal and molecular structure of 1-phenyl-6-(phenylthio)-3H-2,1,3-benzoxathiazolium-3-olate

The crystal structure of 1-phenyl-6-(phenylthio)-3H-2,1,3-benzoxathiazolium-3-olate, C₁₈H₁₃NO₂S₂, has been determined by X-ray single crystal diffraction. The crystals are monoclinic, space groupP2₁,Z = 2, witha = 8.757(2),b = 8.428(2),c = 11.332(3) Å, and = 101.34(2) °. All intensity measurements were made at room temperature on an Enraf-Nonius CAD-4 automatic diffractometer using monochromatized, MoK radiation. The final agreement factorR was 0.029 for 1465 contributing reflections. The nitrophenyl moiety is essentially planar, and the two phenylthio rings are canted at 74 ° and 87 ° to it. There is a possible nonbonded attraction between the nitro group and theortho-sulfur.     

The synthesis and structure of 1,2,3,4-tetrahydro-2,4,4-trimethyl-8-nitroimidazo[1,5-d] [1,2,4]triazin-1-one,C8H11N5O3: A heterocycle with a rare ring system

The title compound (IV) was isolated as a by-product during the course of purification of 4-nitroimidazol-5-(N-methyl)hydrazide (II) by silica gel flash chromatography, employing chloroform-acetone (4:1) as the eluting solvent. The crystals are monoclinic, space groupP2₁/c,a=7.425(1),b=13.615(2),c=10.359(2) Å,=97.66(1)°,d _caled=1.44 g cm^–3, (MoK)=1.06 mm^–1,T=298 K. The number of unique reflections=2401, reflections withI3 (I)=1773;R=0.051,R _w =0.061. The bond distances inIV are: N-N, 1.419(3); N-C(=0), 1.359(3); N(H)-C(CH₃), 1.457(3); N(C)-C(CH₃), 1.501(3); N=C, 1.316(3); C=C, 1.368(3), N-C(=N), 1.353(3); N-C(=C), 1.367(2) Å.     

Structural studies of antihistamines. The crystal structure ofH 4aH 9a -cis-H 9,H 9a-trans-2-methyl-9-phenyl-2, 3,4,4a,9,9a-hexahydro-1H-indeno[2,1-c]pyridine hydrochloride

The crystal and molecular structure ofH _4a ,H _9a -cis-H ₉,H _9a -trans-2-methyl-9-phenyl-2, 3,4,4 _a ,9,9 _a -hexahydro-1H-indeno[2,1-c]pyridine hydrochloride was determined. The compound crystallizes in the orthorhombic space groupPbca, with eight molecules in the unit cell of dimensionsa = 10.461(2),b = 20.141(10), andc = 15.469(3) Å. Intensity data were measured using Mo radiation and a – scan method. The structure was solved by direct methods and refined by least-squares techniques to a finalR of 4.6%. Thecis-trans isomer has higher antihistamine activity compared to thecis-cis isomer but is less active than phenindamine, the 2,3,4,9-tetrahydro derivative. The bond distances in thecis-trans andcis-cis derivatives are identical so that the differences in activity must be related to differences in conformation. The difference in the conformation is discussed from a receptor-site view of the two molecules.     

Reaction of ethyl diazoacetate with Co3(CO)9(μ3-CCl): Isolation and X-ray structures of Co3(CO)9(μ3-CCO2Et), Co3(CO)9(μ3-CCH2CO2Et), and [Co3(CO)9(μ3-CCHCO2Et)]2

The reaction between the tricobalt cluster Co₃(CO)₉(₃-CCl) (1) and AlCl₃, followed by treatment with ethyl diazoacetate, N₂CHCO₂Et, affords a complex mixture of products in low yields. Column chromatography has allowed the isolation of the four cluster compounds Co₃(CO)₉(₃-CH) (2), Co₃(CO)₉(₃-CCO₂Et) (3), Co₃(CO)₉(₃-CCH₂CO₂Et) (4), and [Co₃(CO)₉(₃-CCHCO₂Et)]₂ (5). Clusters 4 and 5 are new and have been fully characterized in solution by IR and ¹H NMR spectroscopy. The molecular structures of clusters 3–5 have also been determined by single-crystal X-ray diffraction analysis. Co₃(CO)₉(₃-CCO₂Et) crystallizes in the triclinic space group P , a = 8.8393(5), b = 14.727(1), c = 15.272(1) Å, = 93.361(6), = 105.509(5)°, = 100.336(6)°, V = 1872.6(2) ų, Z = 4, and d _calc = 1.823 g/cm³. Co₃(CO)₉(₃-CCH₂CO₂Et) crystallizes in the monoclinic space group P2₁/n, a = 9.3806(7), b = 9.2617(8), c = 22.455(2) Å, = 94.483(7)°, V = 1944.9(3) ų, Z = 4, and d _calc = 1.803 g/cm³. [Co₃(CO)₉(₃-CCHCO₂Et)]₂ crystallizes in the monoclinic space group C2/c, a = 21.585(2), b = 8.7977(7), c = 20.784(1) Å, = 104.807(6)°, V = 3815.8(5) ų, Z = 4, and d _calc = 1.835 g/cm³. Plausible pathways leading to the formation of clusters 2, 4, and 5 are discussed.     

Crystal structure,spectroscopic study,molecular modeling,andin vitro antimicrobial activity testing of 2,2′-thiobis[4,6-diphenylpyridine-3-carbonitrile]

The molecular and crystal structures of the title compound have been determined. The crystals are monoclinic:P2₁/n (14),a=11.072(2),b=14.556(2),c=17.569(3)Å, =97.85(1)°.V _c=2805ų,Z=4,D _x=1.285 Mg m^–3, MoK(=0.71069 Å). The molecule adopts a twisted conformation in which the relative orientations of the pyridine nitrogen atoms N101 and N201 with respect to the C–S–C angle are N101-inside. The AM1 and PM3 semiempirical calculations performed agree with the crystal structure. Mass and spectral data (ir. uv,¹H and¹³C nmr) are also reported. Thein vitro tests indicate absence of antimicrobial activity.     

Crystal and molecular structure of 7α, 8α, 13-trihydroxy-marasman-5-oic acid γ-lactone,C15H22O4

The structure of the title compound has been investigated by X-ray diffraction methods. The crystals are monoclinic, space groupP2₁, with cell dimensions:a=9.802(3),b=6.192(1),c=12.392(2) Å, and=112.40(2)°. The structure was solved by direct methods, and refined with 1492 unique reflections by a full-matrix, least-squares procedure givingR=0.0450. Thetrans arrangement of H-8 and H-9 hydrogens as deduced from earlier¹H NMR experiments was fully confirmed by the X-ray investigations.     

Crystal structure and vibrational spectra of two complexes of manganese(II) with glicyne

Two polymeric complexes of glicyne with manganese(II) have been prepared and characterized by means of spectroscopic and x-ray analyses. The first complex of the formula [Mn(Gly)Cl₂(H₂O)₂] crystallizes in the monoclinic space group P2₁/n with a = 6.519(2), b = 15.981(3), c = 7.893(2) Å, and = 97.18(3)°. The Mn atoms are in distorted octahedral environments with all ligands in cis positions. The adjacent manganese(II) ions are linked in polymeric chains via carboxylate groups. The second complex [Mn(Gly)₂Cl₂] crystallizes in the triclinic space group P with a = 4.968(2), b = 6.582(2), c = 7.925(3) Å, = 106.17(3), = 92.86(3), and = 107.21(3)°. The octahedral-coordinated manganese(II) ion is situated on a crystallographic center of symmetry and is bound to four carboxylate oxygen atoms from different glicyne molecules and two chloride ions.     

Synthesis and crystal structure of the two-dimensional coordination polymer catena(bis(μ3-iodo)-(μ 2-pyrazine)-di-copper(I))

The two-dimensional coordination polymer [Cu₂ i ₂(pyz)]_n (where pyz = pyrazine) has been synthesized hydrothermally and structurally characterized by single crystal X-ray diffraction analysis. [Cu₂ i ₂(pyz)]_n crystallizes in the space group P with a = 4.1759(4) Å, b = 7.1281(7) Å, c = 8.1279(8) Å, = 109.607(2), = 101.769(2), = 96.676(2), and Z = 1. The sheet-like polymer is characterized by infinite stair step [Cu₂ i ₂]_n double chains connected in two dimensions through bridging pyrazine ligands. The coordination environment about each copper is approximately tetrahedral having three Cu–I bonds and a single Cu–N bond.     

Crystal structures of two substituted biphenyl derivatives: 5,5′-di t-butyl-2-2′-biphenyldiol and 5,5′-dimethyl-2,2′-biphenyldiol

5,5-Di t-butyl-2,2-biphenyldiol (I), C₂₀H₂₆O₂, crystallizes in the orthorhombic space group P2₁2₁2₁ with a = 18.243(2), b = 9.947(2), c = 9.685(3) Å, and Z = 4; 5,5-dimethyl-2,2-biphenyldiol (II), C₁₄H₁₄O₂, crystallizes in the monoclinic space group P2₁/c with a = 9.959(2), b = 7.932(3), c = 15.392(2) Å, = 105.43(2)°, and Z = 4. The aromatic rings are tilted by 52.7(1) and 43.8(1)° to each other in compounds (I) and (II), respectively. Strong intra- and inter-molecular H-bonds connect the molecules in the crystals.     

Refinement of the crystal and molecular structure of 3,5-diamino-1,2,4-dithiazolium bromide. Comparative investigation on the thiouret hydrohalides

The crystal and molecular structure of 3,5-diamino-1,2,4-dithiazolium bromide has been refined from three-dimensional counter data (856 reflections) by least-squares methods, anisotropically for the nonhydrogen and isotropically for the hydrogen atoms, to a finalR=0.036:a=9.948(1),b=12.731(1),c=5.098(1) Å, B=98.70(1)° at 18°C,Z=4,P2₁/n. The S-S (2.075 Å) distance is intermediate between those of the thiouret hydrochloride and hydroiodide. The C-N(terminal) and C-N(bridging) distances are close to their average value (1.322 Å) within their standard deviations. Thev(NH₂) and (NH₂) frequencies of the thiouret hydrohalides are close to those of dithiobiuret while thev(NH) and (NH) bands are, as expected, absent. Thev(CN) andv(CS) bands are shifted to higher and lower frequencies, respectively, while a newv(SS) broad band is observed in the 430–410 cm^–1 region.     

Crystallographic studies of dihalogeno-tetramethylethylenediamine complexes of zinc,cadmium and mercury. I: crystal and molecular structure of dichloro-(N,N,N′,N′-tetramethylethylenediamine)zinc(II)

The crystal structure of dichloro-(N,N,N,N-tetramethylethylenediamine)zinc(II), C₆H₁₆Cl₂N₂Zn, has been determined from 1684 reflexions measured on a Siemens four-circle diffractometer (A.E.D.) using the /2-scan technique and CuK radiation. The crystals are monoclinic, space groupP2₁/c,a = 7·716(3),b = 13·335(9),c =11·545(5) Å, = 105·59(6) ° andZ = 4. The structure was solved by Fourier methods, and refined by full-matrix least squares to a finalR (conventional) of 6·7 %. Anisotropic thermal parameters were evaluated for the non-hydrogen atoms, but the hydrogen atoms were assigned the equivalent isotropic thermal parameters of the carbon atoms to which they were bonded. The geometry around the zinc atom is distorted tetrahedral, with the Zn-Cl and Zn-N average bond lengths of 2·207(4) and 2·08(1) Å respectively.     

Tonalensin,a 5,10-seco-neoclerodane diterpenoid

We report the X-ray study on the structure of a newseco-neoclerodane diterpenoid, tonalensin, isolated from the aerial parts ofSalvia tonalensis. The compound crystallizes in the monoclinic space groupP2₁ witha=10.146(2),b=7.620(2),c=11.316(2) Å, =109.58(2)°. Thetrans,cis,cis-cyclodeca-1,3,5-triene ring adopts a boat-chair conformation in which the ^1,3,5-triene system is no longer coplanar. The -lactone and furan rings are essentially planar, while both five-membered rings of the dioxabicylooctane moiety arecis-fused and adopt a twist conformation.Contribution No. 1339 of Instituto de Química, UNAM.