Showing papers in "Journal of Chemical Crystallography in 1998"

Structure, absolute configuration, and conformation of the antimalarial compound, Artemisinin

Abstract: The crystal and molecular structure of the antimalarial compound Artemisinin (formerly known as Qinghaosu), C15H22O5 has been determined by direct methods. Crystals are orthorhombic colorless needles, space group P212121, Z = 4. D c = 1.299 g cm −3, with unit cell parameters a = 6.3543(9), b = 9.439(3), c= 24.066(4) A. The molecule incorporates a fused ring system containing a six-membered ring C which includes an oxygen bridge and a peroxy-bridge. The ring C has a distorted boat conformation and the C - O - O - C torsion angle is 47.8(2)°. Rings A and D have symmetrical chair and distorted chair conformations, repectively. Ring junctions A/B, A/D, and C/D are cis, junction B/D is trans. All inter-molecular contacts are van der Waals. The absolute configuration of Artemisinin was determined from the refined value of the Flack x parameter. [The atomic coordinates given in a previous structure analysis, “Crystal Structure and Absolute Configuration of Qinghaosu,” Qinghaosu Research Group, Institute of Biophysics, Academica Sinica, Scientia Sinica, Vol. XXIII No. 3, 380 (1980), do not display the molecule in its absolute configuration.]

A dinuclear cyano-bridged complex based on hexacyanoferrate(III) and samarium(III) nitrate: synthesis and crystal structure

Abstract: A new complex, [Sm(DMF)4(H2O)4Fe(CN)6]·H2O (DMF = N, N-dimethylformamide), has been synthesized and characterized by X-ray single crystal structure and thermogravimetric analyses The complex crystallizes in the P21/n space group, with lattice parameters a = 17583(4) A, b = 8870(2) A, c = 19845(6) A, β = 9598(3)°, V = 3078(1) A3, D x = 1679 Mg m−3, D m = 165(1) Mg m−3, Z = 4 The molecular structure shows that a cyano-bridged bimetallic structure is obtained The Sm atom is coordinated by eight oxygen atoms of four water molecules and four DMF molecules and one nitrogen atom of the bridging cyanide ligand The iron atom assumes approximately an octahedral environment surrounded by six CN ligands The hydrate water molecule is hydrogen-bonded to one of the O atoms bound to Sm Each terminal CN ligand of the Fe(CN) 6 3− entity is hydrogen-bonded to some O atoms of water molecules An infrared spectrum is also reported

Crystal structure of NH 3 (CH 2 ) 2 NH 3 BiCl 5 ·2H 2 O

Abstract: The ethylenediammonium pentachlorobismuthate(III) dihydrate salt is monoclinic with the following unit cell dimensions: a = 10.902(8)A, b = 7.926(6)A, c = 15.199(6)A, β = 96.40(1)°, space group P21/n with Z = 4. The structure shows a layer arrangement parallel to the $$\vec a$$ axis: planes of the [Bi2Cl10]4− bioctahedra alternate with planes of [NH3(CH2)2NH3]2+ dications. The [Bi2Cl10]4− bioctahedra are connected through O(W)–H··· Cl hydrogen bonds, so that infinite unidimensional chains of composition [Bi2Cl10(H2O)2] n 4n− are formed in the structure parallel to the $$\vec a$$ axis. These chains are themselves interconnected by means of the N–H···Cl bonds originating from the [NH3(CH2)2NH3]2+ entities, forming a three-dimensional network.

The crystal structure and IR spectra of μ-(bipyrimidine-N1,N1′,N5,N5′)-bis[(azido-N1)(methanol)(bipyrimidine-N1,N1′)copper(II)] bis(triflate) bis(methanol)

Abstract: The structure of the title compound [Cu2(bipym)3(N3)2(CH3OH)2](CF3SO3)2(CH3OH)2 has been determined by X-ray diffraction. The crystals are triclinic, space group P1, with a = 8.1844(5), b = 11.0253(6), c = 12.9089(7) A, α = 80.249(4), β, = 74.933(5), γ = 74.001(4)°, and Z = 1. The structure consists of a dinuclear Cu(II) unit formed of two didentate bipym ligands, one bis-didentate bipym ligand, two azido anions, and two coordinating methanol molecules. The Cu(II) atom is elongated tetragonally surrounded by two nitrogens of the didentate bipym ligand, one nitrogen of the bis-didentate ligand, and one nitrogen of the azido anion forming the equatorial plane with one nitrogen of the bis-didentate ligand and an oxygen atom of the methanol molecule as the axial atoms. A noncoordinating triflate anion and an additional methanol molecule are also in the crystal lattice and have a hydrogen bond distance of 2.801(3) A with an angle of 157(4)°. The cations link by O – H ··· N bonds into infinite chains running in the c-direction.

Structural and magnetic properties of a syn-anti carboxylate bridged one-dimensional copper(II) complex with ferromagnetic exchange interaction

Abstract: The compound [Cu(phen)(O2CCF3)2]n (phen = 1,10-phenanthroline) has been synthesized and its crystal structure determined. It crystallizes in monoclinic space group C2/c, with a = 19.229(7), b = 11.281(5), c = 7.621(2) A, β = 104.305(12)°, and Z = 4. The crystal structure is polymeric, being built from infinite zigzag chains of trifluoroacetate bridged copper(II), with the phenanthroline ligands being stacked between the chains. The variable-temperature (13–300 K) magnetic susceptibility and ESR data are reported and a weak ferromagnetic exchange interaction is observed with the exchange parameter estimated as J = 2.9 cm−1.

Structure of a 1:1 complex between the anthelmintic drug mebendazole and propionic acid

Abstract: Recrystallization of the anthelmintic drug mebendazole from propionic acid yields a 1:1 molecular complex which crystallizes in the triclinic system space group \({P\bar 1}\), a = 5.928(2), b = 11.066(2), c = 14.337(6)A, α = 94.89(3), β = 101.56(3), γ = 96.18(2)°, and Z = 2 complex units in the unit cell. An x-ray diffraction study revealed an R22(8) hydrogen bonding system in the complex, involving the unprotonated imidazole N and amide N–H function of the drug and the acid carboxylic group. Complex molecules form centrosymmetric dimers by intermolecular N–H···O hydrogen bonding involving the protonated imidazole N atom and the benzoyl O atom of the drug molecule.

Synthesis and structural characterization of a novel polymeric gadolinium(III)–copper(II) complex of iminodiacetic acid

Abstract: A novel polymeric Gd2Cu3 complex of iminodiacetic acid (H2L1=NH{CH2COOH}2), namely, Gd2Cu3(L1)6, 1, has been synthesized and structurally characterized. In the title complex, the Gd3+ ion is nine-coordinated by six O atoms from three bidentate chelating carboxylate groups and three O atoms from three anti-anti bridging carboxylic groups of six L1 ligands; the Cu2+ ion is six-coordinated by four O and two N atoms from two chelating L1 ligands. Each pair of Gd(III) atoms is bridged by three L1 ligands, each of which also chelates with one copper(II) ion, thus forming a Gd2Cu3 cluster unit. Such cluster units are cross-linked by flexible L1 ligands into a three-dimensional coordination framework. The title complex crystallizes in the trigonal space group P-3c1 (No. 165) with a = b = 13.433(4), c = 14.770(6) A; V = 2308(1) A3; Dcalca = 1.859 g cm−3; Z = 2.

Crystal structure of 4,5-dinitroimidazole (45DNI)

Abstract: A single-crystal X-ray diffraction study verified that the target oxidizer molecule, 4,5-dinitroimidazole (45DNI), had been synthesized. Some structural features of 45DNI are discussed and compared with those of 1,4-dinitroimidazole and 2,4 dinitroimidazole. 45DNI crystallizes with two crystallographically unique molecules in the monoclinic space group P21/n (#14) with unit-cell parameters a = 11.5360(8) A, b = 9.071(1) A, c = 11.822(1) A, β = 107.640(6)°, Z = 8, and has a density of 1.781 g/cm3. The molecular packing consists of infinite one-dimensional chains of 45DNI molecules approximately oriented in the ac direction which are linked by two different hydrogen bonds, $$\left[ {{\text{N}}(1) - {\text{ - H(1)}} \cdots {\text{N(31)}}} \right]$$ and $$\left[ {{\text{N}}(11) - {\text{H(11)}} \cdots {\text{N(3)}}} \right]$$ . In the lateral directions the chains are held together by molecular forces.

A new class of flexible energetic salts, part 3: The crystal structures of the 3,3-dinitroazetidinium dinitramide and 1-i-propyl-3,3-dinitroazetidinium dinitramide salts

Abstract: The crystal structures of 3,3-dinitroazetidinium, 1, and 1-i-propyl-3,3-dinitroazetidinium dinitramide, 2, have been determined. 1 crystallizes in the orthorhombic space group Cmc21 with cell dimensions a = 9.932(1), b = 8.545(1), c = 11.107(1) A, while 2 crystallizes in the orthorhombic space group Pbca with cell dimensions a = 11.464(2), b = 11.657(2), c = 17.916(4) A. Compound 2 formed spontaneously from 1 by reacting with the solvent, acetone, during attempts to recrystallize it. The conformations adopted by the dinitramide ions are quite different with the bend, twist, and torsion angles for the dinitramide ion in 1 being much smaller than those in 2. Possible reasons for the dramatic differences in conformations observed in 1 and 2 are the different local symmetries for this ion found in the two structures as well as the absence of hydrogen bonding interactions in 2.

N-o-tolyl-2-hydroxy-1-naphthaldimine and its NiII complex. Conformational changes of free ligand by chelatation

Abstract: The main scope of the paper deals with keto/amine-enol/imine tautomerism in the solid state of an N-aryl substituted naphthaldimine and conformational changes of this ligand after coordinating to the nickel atom. The N-o-tolyl-2-hydroxy-1-naphthaldimine (I) crystallizes in the orthorhombic space group P 212121 with cell dimensions a = 7.8641(4), b = 12.712(1), c = 13.853(1) A and corresponding bis-bidentate nickel complex (II) in the monoclinic space group P 21/c and unit cell dimensions a = 7.436(3), b = 22.050(5), c = 8.643(4) A, β = 95.05(6)°. In the nonplanar molecule of (I) the presence of the enol tautomer is found. In (II) the metal atom has the characteristic square-planar coordination with NiII on crystallographically imposed inversion centers. Two naphthaldimine moieties are not coplanar showing stepped conformation with step height 1.034 A.

Synthesis and X-ray crystallographic characterization of [Cd(NO3)2(15-crown-5)] and [Cd(NO3)2(18-crown-6)]

Abstract: Reaction of 15-crown-5 or 18-crown-6 in 3:1 (v/v) CH3CN:CH3OH with Cd(NO3)2·4H2O followed by slow evaporation produces [Cd(NO3)2(15-crown-5)] or [Cd(NO3)2(18-crown-6)]. Crystals of [Cd(NO3)2(15-crown-5)] are orthorhombic with space group Pbca and cell parameters a = 13.562(5), b = 15.941(9), and c = 15.011(7) A at 295 K. [Cd(NO3)2(18-crown-6)] crystallizes in the monoclinic space group C2/c with a = 11.235(2), b = 11.196(5), c = 15.385(3) A, and β = 99.89(2)° at 295 K. The metal center in [Cd(NO3)2(15-crown-5)] rests atop the macrocyclic donor array with two cis-bound nitrate anions and adopts a distorted tricapped trigonal prismatic geometry. [Cd(NO3)2(18-crown-6)] resides on an equatorial two-fold rotation axis with Cd2+ coordinated in the 18-crown-6 cavity and the nitrate anions oriented in twisted trans positions.

Gallium-complex of anguibactin, a siderophore from fish pathogen Vibrio anguillarum

Abstract: The crystal structure determination of the Ga(III) complex of racemized anguibactin (C15H16N4O4S) confirms the previously predicted chemical structure of this novel siderophore isolated from the fish pathogenic bacterium, Vibrio anguillarum 775. The structure of the complex consists of a dimeric binuclear unit, (C15H14N4O4S·CH3O)2Ga2 which possesses a crystallographic center of symmetry. Each Ga ion forms a distorted octahedral coordination using one of the dihydroxy catechol O atoms, the thiazoline nitrogen, the hydroxamate (N–O) group and the nonprotonated nitrogen atom of the imidazole ring. The coordination sphere is completed by two bridging methoxide oxygen atoms. The dimer is further stabilized by a pair of hydrogen bonds between the second benzohydroxy group and the nitroso oxygen of the hydroxamate group. Crystal data: C15H14N4O4SGa·(CH3O)·(1.5) (CH3OH), monoclinic, P21/n, a = 16.890(4), b = 11.680(3), c = 11.227(3)A, β = 110.29(4)°, V = 2077.4(9)A3, Z = 4, Dcalc = 1.583 g cm−3, λ = 1.54178A.

The isoxazole heterocyclic system : synthesis of a new model structure in immunosuppressing agents

Abstract: A new lead structure in the isoxazole heterocyclic system showing immunosuppressing activity is described. Synthesis, spectral and X-ray data giving evidence of the structures of these compounds are presented. X-ray studies were carried out on compounds I C18H22N4O4 with a = 9.606(3), b = 9.813(3), c = 9.849(3)A, α = 87.28(3), β = 79.06(3). γ = 80.89(3)° Z = 2, and space group $$P\bar 1$$ ; and II C14H15N4O3Cl with a = 7.090(3), b = 16.807(3), c = 12.925(3)A, β = 104.41(3)°, Z = 4 and space group P21/n.

Crystal structure of retro-isomer of the siderophore ferrioxamine E

Abstract: The structure of the retro-isomer of ferrioxamine E sesqui-hydrate, a ferrioxamine E analog in which the N-hydroxy and carbonyl functions are transposed, was found to be isomorphous with that of ferrioxamine E. The interchange of N and C atoms in the three hydroxamate groups seemed to have caused some noticeable differences in the iron-coordination octahedron. The difference in the average Fe–O(N) and Fe–O(C) distances in the retro-isomer, 0.061A, is about one-half of that observed in case of ferrioxamine E, 0.102A. The ligand bite of the two complexes is similar (1.27), the retro-isomer has a smaller (42°) twist angle than that (45°) of ferrioxamine E. Crystal data: C27H45N6O9Fe·1.5H2O, triclinic, \({P\bar 1}\), a = 19.816(8), b = 10.567(8), c = 7.973(5)A, α = 106.54(6), β = 94.99(7), γ = 97.92(6)°, V = 1571.1(12)A3, Z = 2, Dcalc = 1.439g/cm3·λ = 0.71073A.

Structure of tetrahydro-2-naphthyl-4H-1,3,6,2-dioxazaboracine

Abstract: Intramolecular B-N coordination occurs in tetrahydro-2-naphthyl-4H-1,3,6,2-dioxazaboracine, 2: (R = 2-naphthyl; R′ = H) both in the solid state and in CDCl3 solution. Compound 2: (R = 2-naphthyl; R′ = H) crystallizes in the orthorhombic space group P212121 (Z = 4), with a = 9.266(6), b = 11.034(8), c = 12.0635(10) A. Molecules are linked, in the solid state, into spiral chains. As only one of the two oxygen atoms present in each molecule is involved in H-bonding, the boron and nitrogen centres are chiral. The intramolecular B-N bond length is 1.671(4) A; other geometric parameters are B-O bond lengths of 1.448(4) and 1.464(4) A, a B-C bond length of 1.598(4) A, and bond angles at B between 100.6(3) and 115.4(3)°. The δ11B value for 2 (R = 2-naphthyl, R′ = H) at 25°C in CDCl3 solution is 10.7 ppm.

A new class of flexible energetic salts, part 2: The crystal structures of the cubane-1,4-diammonium dinitramide and cubane-1,2,4,7-tetraammonium dinitramide salts

Abstract: The crystal structures of cubane-1,4-diammonium dinitramide, 1, and cubane-1,2,4,7-tetraammonium dinitramide, 2, have been determined. 1 crystallizes in the space group P21/c with cell dimensions a = 6.018(2), b = 11.642(3), c = 9.754(3) A, β = 107.24(2), while 2 crystallizes in the space group P21/c with cell dimensions a = 9.401(4), b = 9.603(3), c = 12.603(4) A, β 111.08(3). In these structures the ammonium substituents are symmetrically attached with respect to the cubane skeleton and have neither low lying empty orbitals nor available lone pairs of electrons thus they have a minimal effect on the metrical parameters of the cubane skeleton. All C–C bond lengths are close to the overall average C–C bond length for all reported cubanes of 1.559 A. The conformations adopted by the dinitramide ions in both structures are quite different, with the bend, twist, and torsion angles for the dinitramide ion in 1 being significantly larger than those found for the dinitramide ions in 2, due to the different types of hydrogen bonding found in the two structures. In 2, the conformation adopted by the adjacent ammonium ions allows two of the three protons from each ammonium cation to form hydrogen bonds in such a manner that they span either the syn or the anti oxygen atoms of a single dinitramide anion. The dinitramide anion is thus constrained by these interactions and is less free to twist and bend. These results provide further confirmation that the metrical parameters of both the cubane and dinitramide moieties are flexible and reflect their local environment.

The crystal and molecular structures of 9,10-dihydro-9, 10-ethano- and etheno-anthracenes

Abstract: As part of our investigation on histamine receptor antagonists, the structures of two 9-10-dihydroanthracene derivatives are reported: 4: C22H28N2; hexagonal, P61; a = 10.014(1), c = 34.556(7) A; V = 3001.0(7)A3; and Z = 6; 9:C19H19N: triclinic, P-1; a = 8.427(2), b = 12.806(3), c = 15.292(3) A, α = 70.27(3), β = 80.83(3), γ = 72.98(3)°; V = 1482.0(6) A3; and Z = 4. All non-aromatic rings in both molecules adopt a similar conformation. However, the three six-membered rings in the etheno-anthracene structure adopt a more regular boat form in spite of two sp2 carbon bridged atoms.

Preparation and crystal structures of the Ce(IV) β-diketonates, [Ce(tmhd) 4 ] and [Ce(pmhd) 4 ] (tmhd =2,2,6,6-tetramethylheptane-3,5-dionate and pmhd = 1-phenyl-5-methylhexane-1,3-dionate)

Abstract: The cerium(IV) β-diketonate compounds [Ce(β-diket)4] [where β-diket = tmhd (2,2,6,6-tetramethylheptane-3,5-dionate) 1, pmhd (1-phenyl-5-methylhexane-1,3-dionate) 2] were prepared by reacting cerium(IV) ammonium nitrate [CAN; Ce(NH4)2(NO3)6] with the respective Na(β-diket) compound in ethanol, and structurally characterized by single crystal X-ray diffraction. Compound 1 crystallizes in the triclinic space group $$P \bar 1$$ with a = 12.472(4), b = 19.972(5), c = 21.436(3) A, α = 97.05(7), β = 90.16(2), γ = 106.55(3)°, V = 5076(2) A3, Z = 4, T = 150(2) K. Compound 2 crystallizes in the monoclinic space group P21/n. with a = 14.817(6), b = 17.123(6), c = 19.146(3) A, β = 105.46(4)°, V = 4682(3) A3, Z = 4, T = 150(2) K. Crystals of 1 contain two independent [Ce(tmhd)4] molecules, with four chelating tmhd ligands bonded to each metal in a distorted dodecahedral arrangement; the cerium atom in 2 is also bonded to four chelating pmhd ligands but in this case the coordination geometry is closer to square antiprism. Both complexes are air and moisture stable. Sublimation studies reveal that 1 sublimes almost quantitatively, while 2 is comparatively involatile.

A new class of flexible energetic salts, part 4 : The crystal structures of hexaaquomagnesium(II), hexaaquomanganese(II), and hexaaquozinc(II) dihydrate salts of dinitramide

Abstract: The crystal structures of the hexaaquomagnesium (1), hexaaquomanganese (2), and hexaaquozinc (3) dihydrate salts of dinitramide have been determined. 1 crystallizes in the monoclinic space group P21/n with cell dimensions a = 9.589(2), b = 7.420(1), c = 11.116(2) A, β = 108.25(3)°, 2 crystallizes in the monoclinic space group P21/n with cell dimensions a = 9.623(4), b = 7.477(2), c = 11.274(3) A, β = 108.38(3)°, and 3 crystallizes in the monoclinic space group P21/n with cell dimensions a = 9.513(1), b = 7.4270(8), c = 11.164(1) A, β = 108.806(6)°. The three structures are isostructural, consisting of hexaaquo cations, dinitramide anions and water molecules interlinked by an extensive three dimensional hydrogen bonding interactions. All oxygen atoms as well as the central nitrogen atom of the dinitramide anion are involved in acceptor hydrogen bonds with neighboring water protons. As a consequence of the constraints imposed by these hydrogen bonds the dinitramide ions are almost planar with average deviations of 0.01 A for 1, 0.03 A for 2 and 0.03 A for 3.

Crystal structures of the cobalt(III), nickel(II), copper(II), and zinc(II) complexes of 2-thio-6-picoline N-oxide

Abstract: Structures of the following compounds have been solved: tris(2-thio-6-picoline N-oxide)cobalt(III), [Co(6MOS)3], orthorhombic, Pca21, a = 17.871(3), b = 14.061(2), c = 15.964(2) A, V = 4011(1) A3, Z = 8, and μ = 1.193 mm−1; bis (2-thio-6-picoline N-oxide)nickel(II), [Ni(6MOS)2], orthorhombic, Pbca, a = 15.602(8), b = 13.606(4), c = 13.348(8) A, V = 2833(4) A3, Z = 8, and μ = 1.655 mm−1; bis(2-thio-6-picoline N-oxide)copper(II), [Cu(6MOS)2], orthorhombic, Pbca, a = 13.914(5), b = 12.984(5), c = 15.663(6) A, V = 2830(2) A3, Z = 8, and μ = 1.836 mm−1; and bis(2-thio-6-picoline N-oxide)zinc(II), [Zn(6MOS)2], triclinic, P − 1, a = 7.9737(8), b = 11.7786(9), c = 7.9206(8) A, α = 104.502(7), β = 104.495(8), γ = 93.445(8)°, V = 691.3(1) A3, Z = 2, and μ = 2.106 mm−1. The steric effect of the methyl group in the six-position of the N-oxide ring is considered in comparing these structures to complexes of 2-thiopyridine N-oxide.

Crystal structure of N-benzylmethylammonium dihydrogen-monophosphate monohydrate, [C6H5CH2NH2CH3]H2PO4·H2O

Abstract: The salt N-benzylmethylammonium dihydrogenmonophosphate monohydrate is monoclinic with the following unit cell dimensions: a = 6.356(1)A, b = 8.385(7)A, c = 11.472(5)A, β = 104.32(1)°, space group P21 with Z = 2. The structure consists of infinite parallel two-dimensional [110] planes built of mutually connected ions and water molecules by strong O–H···O and N–H···O hydrogen bonding. There are no contacts other than normal van der Waals interactions between the layers.

Regiospecific ligand addition to the donor–acceptor compound Ru2(CO)6(bpcd): syntheses and X-ray diffraction structures of Ru2(CO)5L(bpcd) and Ru2(CO)5L[μ-C=C(PPh2)C(O)CH2C}(O)](μ2-PPh2) (where L = PMe3 and tBuNC)

Abstract: Thermal and Me3NO-assisted activation of the donor–acceptor complex Ru2(CO)6(bpcd) (1) [where bpcd = 4,5-bis(diphenylphosphino)-4-cyclopenten-1,3-dione] with PMe3 or tBuNC affords the mono-substituted complexes Ru2(CO)5L(bpcd), as a result of regiospecific ligand attack at the diphosphine-substituted ruthenium center. Solution NMR measurements (1H and 31P) reveal that the PMe3 derivative exists as a noninterconverting mixture of axial (3a) and equatorial (3e) isomers, with the only the equatorial isomer being observed for Ru2(CO)5(tBuNC)(bpcd) (5). Near-UV irradiation of 1 in the presence of added ligand yields Ru2(CO)5L(bpcd), in addition to the known μ2-phosphido complex Ru2(CO)6 [μ-C=C(PPh2)C(O)CH2C(O)](μ2-PPh2) (2) and the corresponding phosphido-substituted complexes Ru2(CO)5L[μ-{C =C(PPh2)C(O)CH2C}(O)]μ2-PPh2)[4 (L = PMe3); 6 (L = tBuNC)]. As with compounds 3a, 3e, and 5, both 4 and 6 exhibit ligand attachment at the diphosphine-substituted ruthenium center. The molecular structures of 3e, 4, 5, and 6 were determined by X-ray crystallography. 3e, as the 1/2 C6H6 solvate, crystallizes in the monoclinic space group C2/c: a = 40.573(3) A, b = 10.2663(9) A, c = 18.347(1) A, β = 95.371(6)°, V = 7609(1) A3 and Z = 8; 4, crystallizes in the monoclinic space group P21/n: a = 10.8241(8) A, b = 18.074(1) A, c = 19.194(1) A, β = 96.968(6)°, V = 3727.3(5) A3, and Z = 4; 5, as the 1/2CH2Cl2 solvate, crystallizes in the monoclinic space group C2/c: a = 40.955(3) A, b = 9.7230(6) A, c = 20.542(1) A, β = 106.596(5)°, V = 7839.2(9) A3, and Z = 8; 6, as the 1/2C5H12 solvate, crystallizes in the monoclinic space group P21/c: a = 21.773(2) A, b = 10.907(3) A, c = 18.744(4) A, β = 114.68(1)°, V = 4045(1) A3, and Z = 4. The site occupied by the PMe3 and tBuNC ligands in these compounds is discussed relative to the steric size/electronic properties of the ancillary ligand and its interaction with the bpcd ligand.

The crystal structures of (p-ClPh)3PO and (p-OMePh)3PO, including an analysis of the P-O bond in triarylphosphine oxides

Abstract: The crystal structures of the compounds tris(para-chlorophenyl)phosphine oxide {(p-ClPh)3PO} and tris(para-methoxyphenyl)phosphine oxide {(p-OMePh)3PO} were determined by X-ray diffraction methods. (p-ClPh)3PO crystallizes in the space group P-1 (no. 2) with a = 11.828(2), b = 12.645(2), c = 14.072(2) A, α = 97.90(1), β = 109.45(1), γ = 115.43(1), V = 1692.3(2) A3 and Z = 4. The mean O–P and C–P distances are 1.481(6) and 1.806(2) A, respectively, and the mean C–P–C angle is 106.5(1.1). (p-OMePh)3PO crystallizes in the space group P21/c (no. 14) with a = 18.8642 (10), b = 10.3999(5), c = 21.3462(16) A, β = 115.414(6)°, V= 3782.6(4) A3, and Z = 8. The mean O–P and C–P distances are 1.484(5) and 1.798(4) A, respectively, and the mean C–P–C angle is 106.5(1.0). These two structures were analyzed along with the previously determined structures of triphenylphosphine oxide {Ph3PO} and tri-p-tolylphosphine oxide {(p-MePh)3PO}, and IR data were collected on all four compounds. Both the observed P–O distances and the IR stretching frequencies for these triarylphosphine oxides support the interpretation of the P–O bond as having substantial multiple-bond character, with a bond order between 1.7 and 1.8. The para-substituents on these triarylphosphines were shown to have a statistically insignificant effect on the P–O bond.

Synthesis and structure determination of a 2D open-framework zincophosphate templated by cyclohexylamine molecules

Abstract: The synthesis and crystal structure of a new bidimensional zincophosphate (ZnPO) are reported. Zn2(HPO4)2Cl2·2NC6H14 crystallizes in the monoclinic space group P21/a (n°14) with a = 8.830(3) A, b = 9.278(3) A, c = 26.950(9) A, β = 90.74(3)°, V = 2207.7(1) A3 and Z = 4. This new material consists of a 2D open-framework of corner sharing ZnO3Cl and PO3OH tetrahedra alternating with planes of protonated cyclohexylamine molecules (NC6H14)+. The organic molecules are interconnected to the framework through hydrogen bonds.

A new class of flexible energetic salts, part 5: The structures of two hexammonium polymorphs and the ethane-1,2- diammonium salts of dinitramide

Abstract: The crystal structures of two hexammonium polymorphs, 1 and 2, and the ethane-1,2-diammonium, 3, salts of dinitramide have been determined. 1 crystallizes in the triclinic space group \({P\bar 1}\) with cell dimensions a = 6.391(2), b = 7.5826(9), c = 10.828(1) A, a = 77.58(1), β = 88.18 (2), γ = 87.54(2)°, 2 crystallizes in the monoclinic space group P21/c with cell dimensions a = 6.4893(3), b = 14.5149(8), c = 10.6557(4) A, β = 94.300(4)°, and 3 crystallizes in the triclinic space group \({P\bar 1}\) with cell dimensions a = 5.614(1), b = 6.867(2), c = 7.371(2) A, α = 68.89(2), β = 89.00(2), γ = 78.90(2)°. The three structures all contain protonated amine cations which are involved in hydrogen bonding interactions with dinitramide anions.

Characterization and structural analyses of trimethoxy and triethoxybenzo[b]thiophene

Abstract: The crystal and molecular structures of two methoxybenzo [b] thiophenes have been determined by three-dimensional, single-crystal X-ray diffractometry. Both 3-(3′,4′,5′-trimethoxybenzoyl)-2-(4′-methoxyphenyl)-6-methoxybenzo[b]thiophene and 3-(3′,4′,5′-triethoxybenzoyl)-2-(4′-methoxyphenyl)-6-methoxybenzo[b]thiophene (hereafter referred to as I and II, respectively) crystallize in the triclinic centrosymmetric space group \(P \bar 1\) (No. 2, C1) with two formula units per cell with a = 6.842(1) A, b = 12.602(2) A, c = 13.815(2) A, α = 94.80(1)°, β = 98.27(2)°, and γ = 100.59(2)° and a = 10.600(1), b = 11.415(2), c = 12.137(2) A, α = 94.57(1)°, β = 101.18(1)°, and γ = 110.45(1)°, respectively. The phase problems were solved by direct methods and the respective final full-matrix least-squares refinements converged to R = 0.039 and 0.068. The structures differ in the orientation of the trimethoxy and triethoxy groups of the benzoyl ligands. The molecules in the crystal lattice are held together by van der Waals forces. Selected bond distances, angles, and torsion angles are tabularized as well as reference to the synthesis of the title compounds and peripheral studies.

Synthesis and crystal structure of a macrocyclic azidotetraamine copper(II) complex

Abstract: The complex [Cu(L)N3](H2O)(ClO4) (1) (L = 3,14-dimethyl-2,6,13,17-tetraazatricyclo[14,4,01.18, 07.12]docosane) has been prepared and characterized by X-ray crystallography. 1 crystallizes in the monoclinic space group P21/c, with a = 8.907(5), b = 20.036(3), c = 14.773(2) A, β = 103.78(2)°, V = 2560.6(15) A3, and Z = 4. The coordination geometry around the Cu(II) ion is a distorted square-pyramidal with four nitrogen atoms of the macrocycle and one nitrogen atom of the axial azido group.

Molecular structures of M(tfac)3 (M=Al, Co) and Cu(H2O)(fod)2 : Examples of unusual supramolecular architecture

Abstract: The molecular structures of Al(tfac)3 (1), Co(tfac)3 (2) (H-tfac = 1,1,1-trifluoroacetylacetone) and Cu(H2O)(fod)2 (3) (H-fod = 1,1,1,2,2,3,3-hepta-fluoro-7,7-dimethyloctane-4,6-dione) have been determined. The metal coordination spheres in compounds 1 and 2 are essentially the same as the respective M(acac)3 derivatives. Despite the isomorphous nature of the structures of compounds 1 and 2, the identity of the nearest intermolecular van der Waals contacts are altered by minor changes in the metal coordination sphere. The geometry about copper in compound 3 is close to that of an ideal square bipyramid with the β-diketonate ligands occupying the basal plane. The water ligand in each molecule of compound 3 is hydrogen bonded to an oxygen of a β-diketonate ligand on an adjacent molecule resulting in the formation of dimers, which form rods along the y-axis due to weak C–F···Cu interactions. Crystal data: (1) orthorhombic, Pca21, a = 14.949(3), b = 19.806(4), c = 13.624(3) A, V = 4033(1) A3, and Z = 8, and (2) orthorhombic, Pca21, a = 14.930(3), b = 19.620(4), c = 13.540(3) A, V = 3966(1) A3, and Z = 8,; (3) monoclinic, P21/c, a = 12.447(3), b = 10.486(2) c = 21.980(4) A, β = 102.65(3)°, V = 2799(1) A3, and Z = 4.

Molecular structure of AlH3[N(CH2CH2)3CH]2

Abstract: Reaction of AlH3[N(CH2CH2)3CH] with hexamethyltrisiloxane, (OSiMe2)3, gives rise to the bis-quinuclidine complex AlH3[N(CH2CH2)3CH]2, which has been characterized by 1H and 13C NMR spectroscopy and X-ray crystallography. The molecular structure of AlH3[N(CH2CH2)3CH]2 consists of a trigonal bipyramidal aluminum with axial coordination of the quinuclidine ligands. Crystal data: orthorhombic, space group Pbcn, a = 10.6895(9), b = 12.266(1), c = 12.3794(9) A, V = 1623.2(2) A3, and Z = 4.

Reaction of bis(dimethoxyphosphino)dimethylhydrazine (dmpdmh) with PhCCo3(CO)9: synthesis and X-ray characterization of the dmpdmh-bridged polymorphs of PhCCo3(CO)7[(MeO)2PN(Me)N(Me)P(OMe)2]

Abstract: The tricobalt cluster PhCCo3(CO)9 reacts with the bis(phosphanyl)hydrazine ligand bis(dimethoxyphosphino)dimethylhydrazine (dmpdmh) to give the monosubstituted cluster [PhCCo3(CO)8]2(dmpdmh) and the disubstituted cluster PhCCo3(CO)7(dmpdmh) as the major products. This latter cluster contains a bridging dmpdmh ligand. Both IR and NMR spectroscopies (31P and 1H) have been employed in the solution characterization of these two clusters. The solid-state structure of PhCCo3(CO)7(dmpdmh) was unequivocally established by X-ray diffraction analysis, which has revealed the presence of two different polymorphs for this particular cluster. The first polymorph crystallizes in the monoclinic space group P21/n, a = 9.7127(7) A, b = 17.025(2) A,c = 16.894(1) A, β = 96.245(5)°, V = 2777.0(4) A3, Z = 4, and dcalc = 1.689 g/cm3; while the second polymorph crystallizes in the orthorhombic space group Pbca, a = 16.925(2) A, b = 16.208(2) A, c = 20.541(3) A, V = 5635(1) A3, Z = 8, and dcalc = 1.665 g/cm3.