Crystal and molecular structure of bis(acetylacetonato) nickel(II)diethanol

The title compound, Ni(C₅H₇O₂)₂· (C₂H₅OH)₂, crystallizes in the triclinic system with unit cell dimensionsa = 8·923,b = 5·283,c = 9·522 Å, = 81·4, = 106·1 and = 103·3 °;Z= 1, space groupP¯1. The structure was solved by Fourier methods, and the 1557 three-dimensional counter diffraction intensity data (CuK) were used in a least-squares refinement to a conventional unweightedR of 0·053. The nickel atom is surrounded by the four oxygen atoms of the two acetylacetone ligands and the two oxygen atoms of the ethanol molecules, forming a tetragonally-distorted octahedron with acetylacetone oxygen atoms at 1·997 and 2·026 Å and ethanol oxygen atoms at 2·140 Å. Parallel molecules are linked into columns along theb-axis by hydrogen bonds between the ethanol oxygen atom of one molecule and an acetylacetone oxygen atom of a neighboring molecule.Presented at the Amer. Cryst. Ass'n. Summer Meeting, Ames, Iowa, Aug. 1971.Taken in part from the M.S. Thesis in Physics of T. S. Burke, Syracuse University, 1971.     

Crystal and molecular structure of tris (2,2,6,6-tetramethyl-3,5-heptanedionato) aquodysprosium(III), Dy(thd)3H2O

The crystal structure of Dy(thd)₃H₂O has been solved by three-dimensional X-ray methods at room temperature. The space group isP¯1 and the cell dimensions area = 14·21(1),b = 14·88(2),c = 11·60(2) Å, = 99·76(3), = 109·91(1), = 114·08(1) °.Z = 2,D _m = l·24 andD _x = 1·238 gcm^–3, respectively. Full-matrix least-squares refinement of atomic and individual isotropic thermal parameters, using 3015 intensities obtained by counter methods, terminated with a conventionalR of 0·058. The oxygen polyhedron around dysprosium has pure seven-coordination geometry, the seventh ligand being the water molecule. The water is hydrogen bonded to two oxygen atoms of a centre of symmetry related formula unit so that two formula units are in fact held together by hydrogen bonds in a dimer.Supported by National Institute for Metallurgy, Johannesburg.     

Crystal and molecular structures of the orthorhombic and monoclinic isomers of catena-di-μ-chloro-semicarbazidecopper(II)

The crystal structures of two isomeric complex compounds of formula [Cu(Cl)₂(NH₂NHCONH₂)] have been determined by X-ray diffraction methods. The orthorhombic isomer has space groupPna2₁ and unit cell constants:a = 6·91(1),b = 8·30(1),c = 10·24(1) Å;Z = 4. The monoclinic isomer has space groupP2₁/c and unit cell constants:a = 6·91(1),b = 8·30(1),c = 11·32(1) Å, = 117·1(2)°;Z = 4. In both complexes coordination around copper is octahedral, with chains of coordination polyhedra along [100]. In the monoclinic compound, the two semicarbazide molecules, which are present in two adjacent octahedra along the chain, have the oxygen and nitrogen atoms in thetrans configuration, one with respect to the other, and are correlated by a centre of symmetry. In the orthorhombic compound, the two semicarbazide molecules are in thecis configuration and there is no centre of symmetry. In both compounds packing is determined by the NH···Cl and NH···O hydrogen bonds which join the chains together.The authors are indebted to Mr M. Lanfranchi who prepared the compounds and to Dr A. Immirzi who made abailable his computer programs.     

Substituted phenols as ligands III: Crystal and molecular structure of bis(4-formyl-2-methoxyphenolato)bis(pyridine)copper(II) monohydrate

Bis(4-formyl-2-methoxyphenolato)bis(pyridine)copper(II) monohydrate crystallizes in the triclinic system:a = 10·432,b = 9·342,c = 13·799 Å, = 103·75, = 100·53, = 100·81 °,Z = 2, space groupP¯1.The structure was determined by Fourier methods with Cuk diffractometer data, and refined by a combination of block-diagonal and full-matrix least squares toR = 0·068 for 2430 observed reflexions.The copper atoms occupy the special positions 0, 0, 0 and 0,1/2, 1/2; hence, both molecules are centrosymmetric. Both the methoxy and phenolic oxygen atoms of the phenolate ions coordinate to the metal. These, together with coordinated nitrogen atoms from the pyridine molecules, give the copper atoms a six-fold coordination.Hydrogen bonding between a water molecule and the phenolic oxygen atoms of adjacent molecules results in chains of molecules linked approximately along [011].     

Crystal and molecular structure of calcium 2,4,6,8-cyclooctatetraene-1, 2-dicarboxylate dihydrate

Calcium 2,4,6,8-cyclooctatetraene-1,2-dicarboxylate dihydrate, CaC₈H₆(COO)₂. 2H₂O, crystallizes in the triclinic space groupP¯1 (C _i ¹) with unit cell dimensions:a = 6·270(3),b = 7·767(4),c = 12·141(7) Å, = 91·10(2), = 100·21(2), = 99·76(2) °;V _c = 572·64 ų,Z = 2,D _m = 1·520(9),D _c = 1·544 g cm^–3. The anion has an approximate 2-fold axis of symmetry to which bond lengths, angles and dihedral angles conform within experimental error. The cyclooctatetraene ring has a tub shape, similar to that found in other cyclooctatetraene structures, with its average bond lengths of 1·46 Å and 1·34 Å for single and double bonds respectively in good agreement with earlier values for similar molecules. The Ca²⁺ cation is coordinated by eight oxygen atoms (six carboxylate, two water) in a distorted tetragonal antiprism with distances ranging from 2·30 to 3·07 Å. All hydrogen atoms were located; the water hydrogens form a layer-like network of hydrogen bonds linking the water and carboxylate oxygens approximately perpendicular to the z axis. The distances range from 2·74 to 2·96 Å.     

Crystal and molecular structure of a root inhibitor fromEucalyptus grandis, 4-ethyl-1-hydroxy-4,8,8,10,10-pentamethyl-7,9-dioxo-2,3-dioxabicyclo [4.4.0]decene-5

The crystal structure of C₁₅H₂₂O₅, a root inhibitor isolated from adult leaves ofEucalyptus grandis, has been determined by direct methods with Cuk diffractometer data and refined by full-matrix least-squares calculations toR = 0·046 for 1829 statistically significant reflexions. The compound, a racemate, crystallizes in the monoclinic space groupP2₁/c, with unit cell dimensionsa = 11·767,b = 12·063,c = 10·906 Å, = 103·2° andZ = 4. The molecular skeleton consists of a 2,3-dioxabicyclo[4.4.0]decene system with one hydroxyl, two carbonyl, one ethyl and five methyl side groups. The dihedral angle at the peroxide bond is 76·8° and the O-O bond distance is 1·480 Å. The molecules are linked in the c direction by hydrogen bonds between the hydroxyl group and one of the carbonyl oxygen atoms.The author is grateful to Professor W. D. Crow for suggesting the problem and for crystals ofG1, to Dr A. McL. Mathieson (Division of Chemical Physics, C.S.I.R.O.), in whose laboratory the data were collected, and Mr J. Fridrichsons for their advice and continued interest, to Dr W. A. Denne (Division of Chemical Physics, C.S.I.R.O.) and Mr B. J. Poppleton (Division of Forest Products, C.S.I.R.O.) for help and advice in the data collection and for the use of data reduction programs and to Dr D. A. Wright (Chemical Physics Group, Department of Supply) for several computer programs used in this work.     

Pentacoordination in dibromo-N-2-methylthiophenyl-2′-pyridylmethyleneiminezinc

The crystal structure of dibromo-N-2-methylthiophenyl-2-pyridylmethyleneiminezinc has been determined and refined by Fourier and least-squares methods toR = 0·058 using three-dimensional X-ray data collected at room-temperature on a single-crystal automated diffractometer. The crystals are triclinic (space groupP¯i), with two molecules in the unit cell of dimensions:a = 9·384(6),b = 11·587(7),c = 7·962(7) Å, = 113·3(1), = 104·3(1), = 92·7(1) °. The zinc atom is five-coordinated through two bromine atoms (Zn-Br=2.366, 2.398 Å), one sulphur atom (Zn-S=2.645 Å) and two nitrogen atoms (Zn-N=2.121, 2.150 Å) from the organic molecule, which behaves as a tridentate ligand. Packing is determined by normal van der Waals interactions.     

Crystal and molecular structure of CI Solvent Yellow 18, 4-(2′,4′-dimethyl phenyl hydrazono)-5-methyl-2-phenyl-3H-pyrazol-3-one

The crystal structure of CI Solvent Yellow 18, C₁₈H₁₈N₄O, has been determined by single crystal X-ray diffraction techniques. It crystallizes in the monoclinic system witha=7.480(2) Å,b=19.184(3) Å,c=11.260(1) Å,=98.00(3)°, space groupP2₁/n andZ=4. The structure has been solved by direct methods, and least-squares refinement has been completed on three-dimensional data (2310 reflections, CuK radiation). The hydrogen atoms have been found, but only their positional parameters refined. Final residual 0.085 (all positive intensity data). The molecule exists as the hydrazone tautomer and intramolecular hydrogen bonding keep the molecule approximately planar. The molecules are packed in layers parallel to the (¯202) plane and in columns parallel tob. Alternate molecules within the columns are in antiparallel. The molecules are linked by van der Waals' forces.     

Precision neutron diffraction structure determination of protein and nucleic acid components. VIII: the crystal and molecular structure of the β-form of the amino acidl-glutamic acid

A neutron diffraction study of the -form of L-glutamic acid, C₅H₉NO₄, has been carried out. The structure is orthorhombic: space groupP2₁2₁2₁,a= 5·159(5),b= 17·30(2),c= 6·948(7) Å andz = 4. Least-squares refinements based on 803 reflexions led to a final conventionalR value of 0·026, and bond lengths involving hydrogen atoms have been determined with an average precision of 0·004 Å. The molecule is in the zwitterion form, and no intramolecular hydrogen bonds have been found. The hydrogen atom involved in a strong hydrogen bond between two carboxyl groups in adjacent molecules (0 ... 0 distance 2·519(2) Å) is covalently bonded to the carboxyl group belonging to the side chain of the amino acid. This side chain is buckled with C gauche to C with respect to the C —C bond. The bond angles involving carbon atoms in the side chain are accordingly strained.Research performed under the auspices of the U.S. Atomic Energy Commission. Part VII is the crystal and molecular structure of the amino acid L-lysine monohydrochloride dihydrate bt T. F. Koetzle, M. S. Lehmann, J. J. Verbist & W. C. Hamilton (Acta Crystallogr, in Press).On leave from Kemisk Institut, Århus Universitet, Denmark, and supported in part by a grant from Statens Naturvidenskabelige Forskningsråd, Denmark.U.S. National Institutes of Health Postdoctoral Fellow.We are indebted to Drs. A. Sequeira, H. Rajagopal and R. Chidambaram for communicating their results for L-glutamicacid hydrochloride prior to publication.     

Crystal structure of 5,5-dimethyl-2-p-bromophenylimino-Δ3-1,3,4-oxadiazoline

Oxidation of acetone-4-p-bromophenylsemicarbazone with lead tetraacetate yields only one isomer of 5,5-dimethyl-2-p-bromophenylimino-³-1,3,4-oxadiazoline, C₁₀H₁₀BrN₃O. Crystals of this compound are triclinic, space groupP¯1,a = 5·91(1),b = 9·52(1),c = 11·59(2) Å, =114·1(1) °, = 93·5(1) ° and = 108·8(1) °;z = 2 and the chemical composition is C₁₀H₁₀BrN₃O. Of 2306 independent reflexions examined, 877 were strong enough to be measured with integrated precession photographs using MoK radiation. The structure was refined using a full-matrix least-squares program to a finalR value of 0·064. The structure consists of planar phenyl and oxadiazoline rings, with a van der Waals interaction between a phenyl hydrogen atom and oxygen atom of the five member ring preventing the two rings from being co-planar; the H(13)-O(1) separation is 2·47 Å. TheZ-configuration of the product suggests a specific mechanism for the ring closure involving an organolead intermediate.     

Studies in molecular structure,symmetry and conformation VI. Crystal and molecular structure of 1-aminocyclopentane carboxylic acid monohydrate

1-aminocyclopentane carboxylic acid monohydrate is monoclinic: space groupP2₁/c,a = 11·24,b = 6·27,c = 11·22 Å and = 97·6 °. The crystal structure was solved by the symbolic addition method and refined to anR factor of 12·1%. The cyclopentane ring is disordered; one of the carbon atoms exists in two alternative sites, leading to two possible conformations both of which are of the envelope type.The authors wish to thank Professor R. Srinivasan for valuable discussions and Professor G. N. Ramachandran for his keen interest. The full-matrix least-squares refinement program used was that of Gantzel, Sparks and Trueblood, modified for the CDC 3600 computer by Zalkin, Lundgren, Liminga and Braenden. The sigma 2 search program used was that of Dr. S. T. Rao. Thanks are due to these individuals for making available their programs. This work was supported in part by Grant NB-05306 to R. Zand from the National Institute of Neurological Diseases and Stroke, National Institute of Health.     

Neutron diffraction study of the crystal structure of phenanthrene

Hydrogen atoms in phenanthrene at room temperature have been located with estimated standard deviations of ±0·07 Å by neutron diffraction analysis. With carbon atoms fixed at positions determined in a previous X-ray analysis, least-squares refinement of limited neutron diffraction data led to anR index of 0·122 over 214 independent observations. An intramolecular contact of 2·03 Å is confirmed for the bay hydrogen atoms H(4) and H(5).We thank Dr J. N. Sherwood for the crystal, and Professor J. Trotter for encouragement. We are grateful to Mr D. H. C. Harris and the University Support Group at A.E.R.E., Harwell, for advice, and to the S.R.C. for making neutron-diffraction facilities available. J.Y. acknowledges a scholarship from Bradford University.     

Heptacoordination in MnII,NiII, and CuII complexes of 2,6-diacetylpyridine bis (acetylhydrazone)

Manganese(II), nickel(II), and copper(II) complexes of 2,6-diacetylpyridine bis (acetylhydrazone) (H₂dapac) have been synthesized and structurally characterized by X-ray diffraction methods. [Mn(H₂dapac) (OH₂)₂](NO₃)₂ crystallizes in the monoclinic space groupP2₁/c witha=11.145(3),b=10.723(4),c=17.189(2) Å, =92.81(2)° andZ=4; [Ni(H₂dapac)(OH₂)₂] (NO₃)₂·H₂O crystallizes in the monoclinic space groupP2₁ witha=9.994(3),b=14.423(4),c=7.697(2)Å, =100.37(2)°, andZ=2; [Cu(H₂dapac)(OH₂)₂](NO₃)₂·H₂O crystallizes in the orthorhombic space groupPbcn witha=20.986(5),b=14.552(3),c=6.905(1)Å andZ=4. In each case the metal atom has a slightly distorted pentagonal bipyramidal environment, the equatorial positions being occupied by three nitrogen and two oxygen atoms from the hydrazone ligand and the apices by two water molecules. The crystalline cohesion in ensured by a three-dimensional network of hydrogen bonds involving the complex cations, the nitrate anions, and, where present, the uncoordinate water molecules.     

Crystal structure of 3-methylrhodaninecopper(I) iodide

The crystal structure of the copper(I) complex has been determined by a three-dimensional X-ray analysis. The monoclinic unit cell, space groupP2₁/c,a = 4·195(1),b = 15·581(2),c = 13·885(2) Å and = 114·9(1) °, contains four formula-units. Intensities were collected on an automatic diffractometer. The structural parameters were refined by full-matrix least-squares methods to a conventionalR value of 0·07 for 1809 non-zero observed reflexions.In this complex, the copper atom is in tetrahedral coordination with three iodine atoms and the sulphur atom of the thiocarbonyl group of the ligand. The iodine atom is coordinated with three copper atoms. The distances are 2·683(2), 2·627(2) and 2·665(2) Å. The distances between neighbouring copper atoms are 3·008(3) and 2·960(3) Å and the corresponding angles are 68·44(6) and 68·02(6) °, suggesting weak copper-copper interactions in this complex.     

Crystal structures of two local anesthetics: Dibucaine·HCl·H2O and Dimethisoquin·HCl·H2O

The crystal structures of the tertiary amine local anesthetics dibucaine hydrochloride monohydrate (C₂₀H₂₉N₃O₂·HCl·H₂O) and dimethisoquin hydrochloride monohydrate (C₁₇H₂₄N₂O·HCl·H₂O) have been determined. Dibucaine forms crystals inP2₁/c witha=10.669(3),b = 35.981(5),c= 11.417(2) Å,= 89.654(3) ° andZ= 8. Dimethisoquin crystallizes in the space groupP¯1 witha = 5.338(6),b=7.579(8),c= 22.336(24) Å,a = 85.513(1), = 87.447(1), =84.863(1) °, andZ=2. Intensity data were collected with an automatic diffractometer, using CuK for dibucaine and MoK for dimethisoquin. The structures were solved using direct methods and refined by full-matrix least-squares procedures to final values ofR= 12.8% for dibucaine andR = 8.8% for dimethisoquin. The structures of both local anesthetics feature planar fused ring systems and extended side chains, one of which contains the tertiary amine that forms hydrogen bonds with other local anesthetic molecules and the chlorine and solvent atoms. The possible sites of action of the anesthetics in the cell membrane are discussed on the basis of these structures.     

Attractive interactions between functional groups in crowded molecules: The solid state structures of diethyl 2-cyano(2′-nitrophenyl)methyltartronate and diethyl (2′-,6′-dinitrophenyl)methyltartronate

The molecular structures of two substituted diethyl tartronates show a variety of interactions between functional groups. Oxygen atoms interact with the electron deficient carbon and nitrogen atoms of nitrile and nitro groups which in response show small distortions from their normal geometries. Short O ··· H contacts between benzyl hydrogen atoms and ortho nitro groups indicate some weak hydrogen bonding effects. Crystal data: C₁₅H₁₆N₂O₇, Mr = 336.3, a = 7.668(2), b = 7.961(3), c = 15.244(3) Å, = 86.78(1), = 81.56(1), = 61.92(1)°, triclinic, P1¯, Z = 2; C₁₄H₁₆N₂O₉, Mr = 356.3, a = 7.786(2), b = 10.324(2), c = 11.155(4) Å, = 71.43(2), = 77.21(2), = 76.40(3)°, triclinic, P1¯ and Z = 2.     

Crystal and molecular structures of two polymeric organotin carboxylates,C5H12O2Sn and C5H9F3O2Sn

The crystal and molecular structures of trimethyltin(IV) acetate and trimethyltin(IV) trifluoroacetate have been determined from three-dimensional X-ray data collected by counter methods using MoK radiation. Both compounds crystallize in the orthorhombic space groupPnma withZ = 4. The acetate hasa = 10·516,b = 8·013,c = 9·706 Å and the trifluoroacetate hasa = 10·567,b = 9·237,c = 9·985 Å. ConventionalR-factors for the two compounds following least squares refinement are, for the acetate, 0·018 (for 731 reflexions) and, for the trifluoroacetate, 0·055 (for 460 reflexions) respectively. The compounds are isostructural and are polymeric with tin atoms linked by carboxylate bridges which are exactly planar. The tin atoms are in five-fold trigonal bipyramidal coordination with the methyl groups in the basal plane and oxygen atoms at the apices. Sn-O interatomic distances are, for the acetate, 2·205(3) and 2·391(4) Å, and for the trifluoroacetate, 2·18(1) and 2·46(2) Å.     

Structure of a novel fluxional molecule: 1,2,3-trithia-[3]-ferrocenophane

The crystal and molecular structure of 1,2,3-trithia-[3]-ferrocenophane has been determined from three-dimensional X-ray data collected by counter techniques. The molecule consists of two nearly parallel, eclipsed cyclopentadienyl rings linked by an S₃ bridge. The material crystallizes in the monoclinic space groupP2₁/c with unit cell parametersa = 9·628(3),b = 9·347(4),c= 11·408(4) Å, = 96·70(3) °. The structure was solved by standard techniques and the least-squares refinement converged to a conventionalR factor of 9·6 %.We wish to thank A. Davison for the gift of the crystals and the U.S. Atomic Energy Commission for financial support.     

Crystal and molecular structure of 2,5-dimethyl-3,4-diacetylfuran

The crystal and molecular structure of 2,5-dimethyl-3,4-diacetylfuran has been determined by direct methods using CuK. photographic data. Refinement by full-matrix least-squares methods gave a finalR factor of 0·097. The crystals are monoclinic: space groupP2₁/c,a =14·92(2),b = 4·09(1),c =16·68(3) Å and = 109·7(5) °;Z = 4. The furan ring of the molecule is planar, and the exocyclic atoms bound to the atoms of the ring lie close to the ring plane. The planes of the acetyl groups are tilted by 16 ° and 47 ° with respect to the ring plane. The exocyclic bond angles of this compound are significantly different from the equivalent angles in furan.     

Crystal structure of 4,6-dinitro-1-(5-tetrazolyl)-1H-indazole trihydrate

The title compound, C₈H₄N₈O₄·3H₂O, crystallizes in space groupP¯1 with cell constantsa=7.022(1),b=9.507(2),c=10.906(2) Å,=84.99(1),=71.89(1),=72.56(1)°,Z=2, andV _c =660.2 ų. The structure was solved by direct methods using diffractometer data and was refined by full-matrix least-squares methods to anR value of 0.060 for 2112 observed reflections. The molecule, consisting of a phenyl ring fused to a pyrazole ring with a tetrazole ring connected to it equatorially, is planar except for the N(7) nitro-group oxygen atoms. The structure is stabilized by a three-dimensional network of O-HO, O-HN, and N-HO hydrogen bonds through the water molecules.