Nucleophilic additions of primary and secondary amines to pentacyclo[5.4.0.02,6.03,10.05,9]undecane-8,11-dione

The crystal structures of three compounds formedvia nucleophilic attack of a heterocyclic secondary amine on PCU-8,11-dione, with the concomitant intramolecular attack of one keto oxygen on the carbon of the other ketone, are presented. In all three compounds, the bridging oxygen contains substantial p-character, and the bonds to the attacking nitrogen are significantly shorter than would be expected.     

Stereospecific solid-state NaBH4-promoted reduction of 1-methylpentacyclo[5.4.0.02,6.03,10.05,9]undecane-8,11-dione

NaBH₄ reduction of a cage dione proceeds in a stereospecific fashion to give theendo,endo-diol. This reactivity is related to the crystal structure.     

Structure of a PCU-derived pinacol formed via sodiumpromoted reductive dimerization of pentacyclo[5.4.0.02,6.03,10.05,9]undecane-8,11-dione monoethylene ketal

The pinacol resulting from sodium promoted reductive coupling of pentacyclo[5.4.0.0^2,6.-0^3,10.0^5,9]undecane-8,11-dione monoethylene ketal possesses a conformation, dictated by intramolecular hydrogen bonding, that lies midway between eclipsed and staggered. The C–C and C–O distances in the pinacol unit are, respectively, longer and shorter than usual, and all parameters are as expected.     

Tetracyclo[6.3.0.04,11.05,9]undecane-2,7-dione

The compound crystallizes in the triclinic space group, , witha=6.7702(4),b=7.0180(4),c=9.1960(7) Å, =92.457(6), =96.150(6), =93.444(5)°, andZ=2. The structure contains a rather short intramolecular H...H contact of 2.26(4) Å.     

Crystal structures of three substituted pentacyclo[5.4.0.02,6.03,10.05,9]undecanes

The crystal structures of three compounds formed via ultimate nucleophilic attack of unsaturated hydrocarbon fragments are reported. Geometries of the bis(vinyl)-, mono(vinyl), and bis(ethynyl)-substituted PCU species are unexceptional. The crystal structures are dictated by the availability of intermolecular hydrogen bonding.     

1H,4H-1,4-Diphenylpyridazino[1,2-α]pyridazine-6, 9-dione

Crystals of C₂₀H₁₆N₂O₂ are orthorombic:P2₁2₁2₁,a = 28.1364(21),b = 7.6474(2),c = 7.5376(2) Å,Z = 4, = 6.4 cm^–1 (CuK radiation), andM = 316.36. The structure has been solved by direct methods and refined by two-block least-squares toR = R _w = 0.042. The conformation of ringB is a distorted envelope at N(10), and the phenyl rings have acis configuration with respect to the pyridazine ring. Thermal motion of the molecule has been analyzed in terms of the rigid-body TLS model.On leave from Departamento de Fisica, Facultad de Ciencias Exactas, U.N.L.P., calle 115 esq. 49, La Plata, Buenos Aires, Argentina.     

Crystal structure of 4-methyl-2-phenylbenzo[de]cyclobut[i] isoquinoline-3,5(2H)-dione

4-Methyl-2-phenylbenzo[de]cyclobut[i]isoquinoline-3,5(2H)-dione, C₂₁H₁₅NO₂, resulted from the photochemical reaction of N-methyl-1,8-naphthalenedicarboximide with phenylacetylene, has been characterized by ¹H NMR, IR, and MS spectra and established by single-crystal X-ray crystallography. The crystal structure belongs to the monoclinic space group P2₁/n with cell parameters a = 12.530(2) Å, b = 9.324(2) Å, c = 13.296(2) Å, = 96.85(1), V = 1542.3(4) ų, and Z = 4.     

The crystal and molecular structures of 3,3,6,6-Tetramethylbicyclo[2.2.1]heptane-2,5-dione and 6,6-Dibromo-1,3,3-Trimethylbicyclo[2.2.2] octane-2,5-dione

The X-ray crystal structures of two bicyclic diketones have been determined. 3,3,6,6-Tetramethylbicyclo[2.2.1]heptane-2,5-dione, C₁₁H₁₆O₂ (A), is monoclinic,C2/c (No. 15), with cell dimensionsa=9.071(3),b=9.748(5),c=12.322(6)Å,=110.15(3)°, andZ=4. The structure was determined by direct methods and refined toR ₁=0.065,R ₂=0.052 for 570 reflections. 6,6-Dibromo-1,3,3-trimethylbicyclo[2.2.2]octane-2,5-dione, C₁₁H₁₄Br₂O₂ (D), is orthorhombic,Pcab, (No. 61), with cell dimensionsa=11.206(3),b=18.818(6),c=11.695(4) Å, andZ=8. The structure was solved by the heavy-atom method and refined toR ₁=0.070,R ₂=0.065 for 1210 reflections. Bond lengths and angles within both structures do not differ from those in similar structures. The opening up of the internal ring angle of the ketone inA (vs. a normal bicyclo[2.2.1]heptane) and the consequent decrease of the adjacent internal ring angle brings the ketone carbon atoms nearer to the hydrogen atoms of the bridging methylene group.     

Cluster self-organization of TR,Ge-containing crystal-forming systems: Suprapolyhedral precursors and self-assembly of La3Ga[6]Ga 4 [4] Ge[4]O14 (langasite) and La3Ge[6]Ge 2 [5] Ge 2 [4] Ga[4]O16 gallogermanates

A combinatorial-topological analysis of the La₃Ga^[6]Ga ₄ ^[4] Ge^[4]O₁₄ and La₃Ge^[6]Ge ₂ ^[5] Ge ₂ ^[4] Ga^[4]O₁₆ gallogermanates, which have MT and MPT microporous frameworks composed of M octahedra (GeO₆, GaO₆), T tetrahedra (GeO₄, GaO₄), and P pyramids (GeO₅), is performed using the method of coordination sequences with the TOPOS 3.2 program package. It is established that the La₃Ga^[6]Ga ₄ ^[4] Ge^[4]O₁₄ gallogermanate is characterized by a crystal-forming net 6 6 6 (of the graphite type). A new type of the binodal net 6 10 1 0 + 6 10 (2: 1) is revealed in the La₃Ge^[6]Ge ₂ ^[5] Ge ₂ ^[4] Ga^[4]O₁₆ gallogermanate. The cyclic cluster precursors composed of six polyhedra with a lanthanum template atom at the center of the LaMT ₅ and LaMP ₃ T ₃ clusters are identified by the two-color decomposition of the nets in the structures of the La₃Ga^[6]Ga ₄ ^[4] Ge^[4]O₁₄ and La₃Ge^[6]Ge ₂ ^[5] Ge ₂ ^[4] Ga^[4]O₁₆ gallogermanates. The coordination numbers of the cluster precursors in these structures are found to be equal to 6 and 4 for two-dimensional nets and 8 and 6 for three-dimensional nets, respectively.     

Crystal and Molecular Structure of the Smectogen 1-[4-n-heptylbenzoyl]-2-[cyanoacetyl]-hydrazine

The compound 1-[4-n-heptylbenzoyl]-2-[cyanoacetyl]-hydrazine crystallizes in the triclinic space group Pl̄ with two molecules in the unit cell and the lattice parameters a = 4.702, b = 8.640, c = 20.906 Å, a = 97.50, β = 92.79, γ = 100.19°. The structure was solved by direct methods and refined by full-matrix least squares calculations to the final residual value R = 0.039.     

Calorimetric investigations of 2-[4-n-alkylphenyl]-5-[4-n-alkyloxyphenyl]-pyrimidines

We investigated temperatures and enthalpies of the phase transitions by means of the calorimeter DSC-2. The kinetics of polymorphic transitions in the solid state, the pretransitional behaviour in the liquid crystalline phases and the transition enthalpies, ranging from 3 J/mol up to 50 kJ/mol, in relation to the occurrence of the liquid crystalline phase types S_G, S_F, S_C, S_A, and N are points of discussion.     

Synthesis and Crystal Structure of 5,7,12,13b,13c,14-Hexahydro-1,4,-dibromo-8,11-dimethoxy-13b,13c-bis(ethoxycarbonyl)-6H,13H-5a,6a,12a,13a-tetra azbenz[5,6]azuleno[2,1,8-ija]benz[f]azulene-6,13-dione

The title compound has been synthesized by the reaction of 4 with 1,4-dimethoxybenzene. The yielded product 5 was investigated with X-ray crystallographic, NMR, EI-MS, and IR techniques. The crystal belongs to a monoclinic system, space group P2₁/c with unit cell parameters a = 12.7790(17) Å, b = 21.565(3) Å, c = 12.2544(16) Å, α = 90°, β = 107.014(2)°, γ = 90°, V = 3229.3(7) Å³, Z = 4, D_c = 1.661, M_r = 807.32, μ = 2.732 mm^?1, F(000) = 1632, R₁ = 0.0540 and wR₂ = 0.0989.     

Crystal Structure of 3-[1-(4-Methylphenyl)-9,10-dihydro-4-azaphenanthren-3-yl]benzo[f]coumarin

Crystallography Reports - The crystal structure of the title compound is determined by single crystal X-ray structure analysis. The structure was solved by direct method and refined to a final...     

4-(E)-2-[3-(3-[(E)-2-(4-cyanophenyl)-1-diazenyl]perhydrobenzo[d]imidazol-1-ylmethyl)perhydrobenzo[d]imidazol-1-yl]-1-diazenylbenzonitrile: X-ray crystal structure

4-(E)-2-[3-(3-[(E)-2-(4-Cyanophenyl)-1-diazenyl]perhydrobenzo[d]imidazol-1-ylmethyl) perhydrobenzo[d]imidazol-1-yl]-1-diazenylbenzonitrile (1) has been synthesized by reac- tion of p-cyanobenzene diazonium chloride with a mixture of formaldehyde and trans-1,2-cyclohexanediamine. The crystal structure has been determined by single crystal X-ray diffraction analysis. The bis-triazene (1) does not adopt a folded conformation, unlike previously studied ethylenediamine analogues, and there is no indication of -stacking in the crystal packing. The dominant interaction between molecules is the van der Waal's attraction between cyclohexane rings. This result establishes the structure of the product of this diazonium coupling reaction as the 1-(1-imidazolidinylmethyl)imidazolidine derivative and not the alternate tetraazabicyclo[4.4.1]undecane derivative. Crystal data: 1 C₂₉H₃₄N₁₀, orthorhombic, space group Pbca, a = 17.946(1), b = 13.106(1), c = 24.108(1) Å, V = 5670.6(3) ų, for Z = 8.     

Crystal structure of 2-N,N-diethylamino-3-carbomethoxynaphtho[2,3-b]thiophene-4,9-dione,C18H17NO4S

The structure of the title compound has been determined with CuK diffractometer data by direct methods and Fourier syntheses, and refined by full-matrix least-squares toR= 0·059 for 1484 observed reflexions. The crystals are monoclinic,a = 8·273(1),b = 15·115(2),c= 13·465(2) Å, = 98·40(2) °,Z = 4, space groupP2₁/c. The ring system is planar, and the bond lengths and angles are close to normal values.We thank Dr M. E. Kuehne for suggesting the problem and for crystals, the National Research Council fo Canada for financial support and the University of British Columbia Computing Centre for assistance.     

Crystal structure of 4-[benzylideneamino]-3-thiophen-2-yl-methyl-4,5-dihydro-1H-[1,2,4]triazole-5-one

The crystal structure of the title compound C₁₄H₁₂N₄OS was determined by the X-ray diffraction method. The compound crystallizes in the triclinic space group $P\bar 1$ with Z = 2. The molecule is not planar: the dihedral angle between the triazole and thiophene rings is 73.98(2)°, and that between the triazole and benzene rings is 4.05(2)°. The thiophene ring is disordered over two positions, which are approximately parallel and oppositely oriented. The major component refined to a site-occupancy factor of 0.573(3). An intramolecular C-H...O hydrogen bond generates an S(6) ring motif. In the crystal, molecules are linked together by two pairs of N-H...O interactions (to the same O atom as acceptor), forming inversion dimers. The crystal packing is also stabilized by π-π interactions [centroid-centroid distance is 3.978 Å].     

Crystal Structures of N-[2-(4-oxo-4H-benzo[d] [1, 3]-oxazin-2-yl)benzamide and Propionamide and Their N-Containing Analog N-[2-(4-oxo-3,4-dihydroquinazolin-2-yl)phenyl]propionamide

Crystallography Reports - Specific features of the molecular and crystal structures of two substituted benzoxazinones (I and II) and their structural analog quinazolinone (III) have been analyzed...     

Crystal structure of 2,8,14,20-tetranaphthylpyrogallol[4]arene

The aromatic derivative 2,8,14,20-tetranaphthylpyrogallol[4]arene was synthesized by the acid catalyzed condensation of 2-naphthaldehyde and pyrogallol in refluxing aqueous ethanol. Single crystal X-ray analysis revealed that the molecule crystallizes in a triclinic space group P1(bar) No. 2, with a = 11.3396(7) Å, b = 15.9942(10) Å, c = 26.3653(17) Å, α = 94.309(2)°, β = 91.765(2)°, γ = 93.892(2)°, D _calc = 1.298 g/m³ for Z = 1. Within the unit cell, six methanol molecules of crystallization plus one molecule of pyrazine were found to accompany the pyrogallol macrocycle. In the solid state, the macrocycle is found to adopt the chair conformation.