X-ray crystal structure of the 1∶2 triethyleneglycol dimethyl ether (triglyme): Dichloropicric acid adduct

The anhydrous 12 triglyme:Dichloropicric acid adduct is triclinic, space group ; at 24°Ca=8.703(5),b=10.381(4), c=10.404(3) Å, =114.42(3), =99.69(5), =106.40(6)°,D _x=1.656 g cm^–3, V = 776(2)ų,Z=1. Bond lengths and angles are normal except that one C–C–O–C torsion angle in the triglyme is approximately 90° rather than the expected 60 or 180°. Each phenolic OH group hydrogen bonds with a terminal OCH₃ of the polyether. The O...O distance, 2.557(3) Å, is in fair agreement with the 2.52 Å estimated from the single observed IRv (OH) stretch at 1714 cm^–1.     

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.     

Molecular complexes of sulfonamides. 3. Structure of 5-methoxysulfadiazine (form II) and its 1∶1 complex with acetylsalicylic acid

The X-ray structure of the biologically most active polymorph (Form II) of 5-methoxysulfadiazine (1) and that of the 11 complex between this sulfonamide and acetylsalicylic acid (2) are reported. The polymorph1 is monoclinic, space groupP2₁/c witha=13.086(2) Å,b=5.583(1) Å,c=17.222(3) Å, =99.98(1)°,Z=4 and occurs as centrosymmetric hydrogen bonded (N–H...N) dimers in the crystal. This arrangement differs from that observed in other polymorphs of the drug. Complex2 is triclinic, ,a=8.102(1)Å,b=12.033(1) Å,c=12.170(2) Å, =111.67(1)°, =93.77(1)°, =103.82(1)°,Z=2. Complexation involves linear intermolecular hydrogen bonds, N–H...O=C and N...O–H, between the amide group and pyrimidinyl N atom of the sulfonamide and the carboxylic group of the acetylsalicylic acid. On complexation to form2, neither molecular component undergoes any major structural change.     

Crystal and molecular structure of the H-bonded complex between 1-chloro-2-hydroxynaphthalene-3-carboxylic acid and dimethylformamide (1∶1)

Crystal structure determination of the title complex reveals that the dimethylformamide solvent is bound to the carboxylic function of the hydroxy acid, in the form of a 7-membered hydrogen-bonded loop involving both the expected O-HO and an apparently weak C-HO interaction between host and guest. There is a strong intramolecular hydrogen bond between the phenolic OH and the carbonyl oxygen. Close packing of the complex units is afforded by a herringbone type alignment of host molecules.     

Isolation and crystal structures of 1∶3 molecular complexes of triethylenediamineN,N′-dioxide with hydrogen peroxide and water

Two crystalline adducts have been isolated from the reaction of triethylenediamine with aqueous hydrogen peroxide and characterized by X-ray crystallography. ComplexI, ON(CH₂CH₂)₃NO·3H₂O₂, crystallizes in space groupP4₁2₁2 witha=6.772(1),c=23.664(3) Å, andZ=4. The triethylenediamineN,N-dioxide molecule occupies a site of symmetry 2, as does one of the two independent hydrogen peroxide molecules which exhibits orientational disorder. In the crystal structure, both molecular components are linked by hydrogen bonds to form a three-dimensional network. Crystals of compoundII, ON(CH₂CH₂)₃NO·3H₂O₂, belong to space groupPca2₁, witha=15.397(1),b=7.126(2),c=9.030(4) Å, andZ=4. TheN,N-dioxide and water molecules form hydrogen-bonded corrugated layers spaced between the (200) family of planes. The structures have been refined toR _F values of 0.065 (I) and 0.049 (II) using, respectively, 1171 and 747 observed MoK data.     

X-ray crystal structure of DL-aspartic acid-β-hydroxamic acid (N-hydroxyasparagine) monohydrate

The structure of DL-aspartic acid--hydroxamic acid (N-hydroxyasparagine, Asp--ha) monohydrate C₄H₁₀N₂O₅ (HOOCCH(NH₂)CH₂C(O)NHOH×H₂O) has been determined by single-crystal X-ray diffraction methods. The crystals are orthorhombic:P2₁ nb(C _2v ⁹ ),a=9.690(2),b=8.936(2),c=8.118(2) Å,Z=4. The structure has been solved by direct phase determination methods, and refined to an R value of 0.026 for 797 nonzero independent amplitudes. The molecule of the title compound exists in the structure as a zwitterion,^–OOCCH(NH ₃ ⁺ )CH₂C(O)NHOH. The crystal structure is stabilized by intermolecular OH-N and OH-O hydrogen bonds involving amino groups, carboxyl groups and water molecules.     

Sterically constraining photoluminescence. X-ray crystal structure of a bulky platinum(II) α-diimine complex

The photoluminescence study of a series of platinum(II) -diimine complexes revealed a dramatic decrease in steady-state phosphorescence intensity when the diimine ligand was substituted in the 2 and 9 positions. Therefore, the molecular structure of the complex Pt(2,9-dmp)(mes)₂ (where mes = 2,4,6-trimethylphenyl, and 2,9-dmp = 2,9-dimethyl-1,10-phenanthroline) was determined by X-ray diffraction methods: monoclinic, space group P2₁/N, a = 7.9335(7), b = 21.952(3), c = 15.3103(3) Å, = 93.4980(5), Z = 4, R = 0.070, R _w = 0.045. The complex has significant distortions from the ideal square planar geometry which may be responsible for the lack of detectable phosphorescence as compared with those complexes lacking substituents in the 2 and 9 positions on the diimine ligand.     

Structure and spectroscopic properties of the 1∶2 complex of 3,5-dimethylpyridine with 3,5-dinitrobenzoic acid and its deuterated analog

The structure of the nondeuterated and deuterated complexes of 3,5-dimethylpyridine with 3,5-dinitrobenzoic acid in a stoichiometric ratio 12 have been determined by X-ray diffraction methods. The crystals of the nondeuterated complex are triclinic, space groupP¯1 witha=9.409(9),b=10.813(7),c=12.310(7)Å,a=95.75(5),=108.17(7), =91.46(7)° andZ=2. The crystals of the deuterated complex are monoclinic, space groupP2₁/c, witha=11.680(6),b=8.451(4),c=24.382(9)Å,=102.94(4)° andZ=4. Both structures have been solved by direct methods and refined toR=0.035 for 2235 and toR=0.044 for 1938 independent reflections for nondeuterated and deuterated crystal, respectively. The structures consist of 3,5-dimethylpyridinium cations and hydrogen (or deuterium) bis(3,5-dinitrobenzoate) anions. The N(1)⁺-H(N1)O(1)^–, O(7)-H(7)O(2), N(1)⁺-D(1)O(l)^– and O(7)-D(7)O(2) bond lengths are 2.644(4), 2.499(3), 2.739(5), and 2.526(5)Å, respectively. The IR spectra of both complexes within the proton (or deuteron) absorption range have been studied.     

Structure of the 1∶1∶1 complex between 1,4,7,10,13,16-hexaoxacyclooctadecane (18-crown-6), 2,3-dichlorophenol,and water

The structure of the title compound, C₁₂H₂₄O₆·C₆H₄OCl₂·H₂O, has been determined by X-ray diffraction methods. The crystals are monoclinic, space groupP2₁ witha=8.628(2),b=13.767(4),c=9.676(2), =96.38(2)°, andD _x =1.295 Mg m^–3 forZ=2; 2355 reflections were recorded on a CAD4 diffractometer using CuK radiation atT=243° K. The structure was solved usingMultan andShelx. The finalR value based on 1901 reflections is 0.071. The 18-crown-6 molecule has approximatelyD _3d symmetry. The host molecule (18-crown-6), the guest molecule (dichlorophenol), and water form a super-molecule. Binding between host and guest is effected by bridging water molecule: the water and dichlorophenol molecule are linked by a very strong hydrogen bond (OO=2.58 Å); weaker interactions exist between water and oxygens of the crown ether (OO distances 2.85 and 2.90 Å).     

The crystal structure of the molecular complex of 2′,6′-dimethoxyflavone with picric acid: Alternating π-stacking and hydrogen-bonding interactions

The title complex is monoclinic with a = 15.100(5), b = 7.624(3), c = 39.997(15) Å, = 99.49(4)°, Z = 8, and space group P2₁/c. There are two geometrically independent, hydrogen-bonded pairs of molecules in the asymmetric part of the structure. Picric acid and 2,6-dimethoxyflavone are held together by hydrogen bonding between the hydrogen of the phenol group and the oxygen of the carbonyl. Additionnally, this hydrogen forms an intramolecular hydrogen bond with the O atom of an ortho-nitro group. Moreover, a stacking interaction is observed between the -benzopyrone portion of the flavone and picric acid.     

Structure and molecular chirality of the 2∶1 salt of quinine with biphenyl 2,2′-dicarboxylic acid (diphenic acid)

The molecule of the salt consists of two quinine cations and a biphenyl 2,2-dicarboxylic dianion. Both of the quinine cations are protonated at the nitrogen atoms of the quinuclidine fragments. Each carboxylic group of the diphenic dianion acts as a proton donor with respect to the quinuclidine N(1) atom of one of the quinine cations, and as a proton acceptor with respect to the carbinol O(12)-H(12) group of the other. Thus, the interlocking hydrogen-bond system forms a rigid structure. The molecular conformation around the C(8)-C(9) bond is synclinal. The conformational parameters of the diphenic dianion are considerably different from those of diphenic acid in solid state. The absolute configuration of the biphenyl 2,2-dicarboxylic dianion (S) is defined by the positive torsion angle around the line which connects the centers of both phenyl rings. The molecular chirality of the salt arises from the coupling between the quinoline and the biphenyl chromophores, as well as from the coupling of the quinoline-quinoline long-axis polarized-band transition moments.     

Model of the crystal structure of Np(VI) sulfate with dimethyl sulfoxide, NpO2SO4 ⋅ 2SO(CH3)2 ⋅ H2O

A new complex compound, neptunium(VI) sulfate, was grown from aqueous solutions and studied by the methods of X-ray structure analysis. The model of the crystal structure was determined by direct methods within the sp. gr. P2₁ and was refined in the anisotropic approximation (R = 6.2%, 1044 independent reflections). The structure is built by tetragonal and hexagonal Np bipyramids. A hexagonal bipyramid can be considered as a polyhedron derived from a pentagonal bipyramid, in which one equatorial O atom is replaced by two atoms located above and below the equatorial plane. The polyhedra are linked in chains through S-tetrahedra. The chains are linked into a three-dimensional framework by hydrogen bonds with the participation of DMSO groups.     

Mercury(II) complex with terpyridine: structure of the 2∶1 solvate of [Hg(terpy)2](CF3SO3)2 with acetone

[Hg(terpy)₂](CF₃SO₃)₂·0.5(CH₃)₂CO crystallizes in the triclinic space group witha=14.631(6),b=15.258(4),c=18.785(7) Å, =69.66(2), =70.72(1), =88.55(1)°. The crystal structure consists of two independent [Hg(terpy)₂]²⁺ cations, four trifluoromethanesulfonate anions and an acetone molecule in the asymmetric unit. Each mercury atom is coordinated by two tridentate terpyridine ligands forming an irregular six-coordination polyhedron. The Hg–N bond lengths range from 2.27(2) to 2.53(2) Å.     

Synthesis and crystal structure of Nd(III)–Zn(II) complex

A novel heteronuclear complex, [NdZn₂L₆(NO ₃)(phen)₂] (HL = -methylacrylic acid, phen = 1,10-phenanthroline), was synthesized and characterized by elemental analysis, infrared absorption spectra (IR) and its molecular structure was also determined by X-ray structure analysis. The title complex contains a discrete trinuclear ZnNdZn molecule bridged by carboxylate groups between Zn and Nd ions and crystallizes in space group P¯1 with the cell dimensions: a = 13.601(3) Å, b = 16.859(2) Å, c = 12.575(2) Å, = 110.09(1), = 112.21(1), = 81.10(2).     

Synthesis and crystal structure of a polymeric erbium(III)–sodium(I) coordination complex of picolinic acid N-oxide

A new Er(III)–Na(I) coordination polymer of stoichiometry [NaEr₂L₅(H₂O)₆(NO₃)](NO₃)·3.5H₂O (HL = picolinic acid N-oxide) has been synthesized and characterized by single-crystal X-ray analysis. Crystals are triclinic, P with a = 9.823(2), b = 12.453(2), c = 20.643(4) Å; = 98.49(3), ( = 101.40(3), = 108.69(3)°; V = 2284(1) ų; Z = 2. Of the two independent eight-coordinate erbium(III) ions in this complex, one is surrounded by four bidentate chelating L ligands, and the other by one bidentate chelating L ligand, four aqua ligands and two anti-carboxylate oxygen atoms from two neighboring [ErL₄] units. The sodium(I) ion is in a distorted octahedral environment, being coordinated by a unidentate nitrate anion, three aqua ligands and two anti-carboxylate oxygen atoms from two adjacent [ErL₄] units. The complex is built from zigzag chains of syn-anti carboxylate-bridged erbium(III) moieties directed in the a direction, which are cross-linked pairwise by aqua-bridgeddimericsodium(I) units. The resulting composite polymeric chains are further connected by hydrogen bonds to form a three-dimensional network.     

Heteropolymetallic complexes of 1,1′-bis (diphenylphosphino)ferrocene,dppf. VIII. X-ray crystal structure of copper(I) dimer [(μ-dppf)(Cu(dppf))2](ClO4)2 1

The dimeric Cu(I) complex [(-dppf)(Cu(dppf))₂](ClO₄)₂, where dppf is Fe((n⁵-C₅H₄)P-(C₆H₅)₂)₂, has been characterized by single-crystal X-ray crystallography. The complex crystallizes in the triclinic space groupP1 (no. 2) with unit cell parametersa=21.852(5),b=18.063(5),c=14.867(5)Å, =114.32(3), =109.87(3), =82.84(3)°. The structure was refined toR=5.40% based on 5562 observed reflections. Two crystallographically independent, structurally equivalent, units were observed in the structure. The structure consists of the centrosymmetric dimeric [(-dppf) (Cu(dppf))₂]²⁺ cations and ClO^4/– anions. The copper atoms are three-coordinate being trigonally bonded to one chelating and one bridging ligand. The P-Cu-P bond angles for the chelating dppf ligand are 111.1(2)° and 111.3(2)°, while the P-Cu-P angles linking different dppf molecules range from 123.9(2) to 124.2(2)°. Cu-P bond distances fall within normal ranges lying between 2.265(5) and 2.285(4)Å, with the values for the chelating dppf being slightly larger than those observed for the bridging ligand. The cyclopentadienyl rings are exactly staggered and parallel, and the P atoms 180° opposed in the bridging dppf, while the rings maintain an approximately staggered configuration and are inclined by 1.6° to each other with the P atoms being 39.5° apart in the chelating ligand. A steric control of the stereochemistry of the monomer fragment of the dimer complex is suggested.Presented at the XXVIII International Conference on Coordination Compounds, Gera, FRG, 1990; see Abstracts No. 6-31.     

Spectroscopic studies and crystal structure of (E)-N′-(2-hydroxy-3-methoxybenzylidene)isonicotinohydrazide

The structure of compound has also been examined cyrstallographically. It crystallizes in the monoclinic space group P2₁/c with a = 7.673(1), b = 16.251(2), c = 10.874(1) Å, β = 110.42(1)°, V = 1270.7(3) ų, D _x = 1.418 g cm^?3, R ₁ = 0.0349 and wR ₂ = 0.0935 [I > 2σ(I)], respectively. The title compound has been synthesized from the reaction of isonicotinohydrazide with 2-hydroxy-3-methoxybenzaldehyde. It has been characterized by using elemental analysis, MS, IR, ¹H NMR, ¹³C NMR and UV-Visible spectroscopic techniques.     

Synthesis,crystal structure and spectral studies of the complex [Ni(C3H4N2)4(H2O)2]·(C6H4COSO2N)2

The title compound has been synthesized and its crystal structure determined at room temperature.M _r =731.39, triclinic, space groupP¯1,a=9.020(3),b=11.280(7),c=7.784(2)Å,=97.05(4),=97.08(2), =105.32(4)°, U=748(1)ų,Z=1,D _calc.=1.624 g/cm³. The finalR is 0.030 for 3095 independent observed reflections withI3(I). The crystal structure consists of repeated [Ni(im)₄(H₂O)₂]²⁺ cations and noncoordinated saccharin anions. In the complex cation [Ni(im)₄(H₂O)₂]²⁺, Ni² is bonded to four N atoms from four imidazole molecules and two O atoms from two water molecules forming an approximately square octahedral stereochemistry. The d-d transition spectrum of the title compound is also reported and is explained perfectly with the scaling radial theory which was proposed by us.     

Crystal and molecular structure of the inclusion compound between 1,1′-binaphthyl-2,2′-dicarboxylic acid and acetylacetone (1∶1)

The lattice type crystalline inclusion compound of 1,1-binaphthyl-2,2-dicarboxylic acid (BNDA) with acetylacetone (AcAc) 11 has been investigated by single crystal X-ray diffraction. AcAc is present as the enolic tautomer, stabilized by a notably short intramolecular hydrogen bond. This H-bond closes a six-membered ring with delocalization of the system of conjugated double bonds. In the crystal the AcAc molecules are incorporated into channels, delimited by bulky binaphyl moieties, in a hydrogen-bonded framework of BNDA, and they do not show any disorder. The strictly stoichiometric host:guest ratio seems to be enforced by packing forces only.     

Crystal structure of the addition compound of N,N′-bi(2-pyridylmethyl)-oxamide and complex of manganese with 1,10-phenanthroline

The structure of the addition compound, Mn(phen)₃(PMoxdH₂)(ClO₄)₂ was established by X-ray crystallography, where PMoxdH₂ is N,N-bi(2-pyridylmethyl)-oxamide. Six nitrogen atoms of the three 1,10-phenanthroline bind to the manganese ion and the oxygen atom of PMoxdH₂ is uncoordinated. The addition compound crystallizes in the monoclinic space group C2/c, with lattice parameters a = 23.780(6), b = 11.948(5), c = 18.466(6) Å, = 117.38(3)°, V = 4659(3) ų, and Z = 4.