Network hydrogen bonding: the crystal and molecular structure of cubane-1,3,5,7-tetracarboxylic acid dihydrate

The structure of cubane-1,3,5,7-tetracarboxylic acid dihydrate (1) has been determined. It crystallizes in the space groupP2₁/c with cell dimensionsa=6.503(1),b=19.173(1),c=10.527(1) Å, β=101.60(1). The details of this structure have reaffirmed the fact that the cubane skeleton is a flexible entity which reflects its steric and electronic environment. Of the four carboxylic acid groups three adopt asyn conformation while the fourth adopts ananti conformation. The orientation of these groups with respect to the cubane skeleton is reflected in the C?C bond lengths. Those C?C bonds which are perpendicular to the carboxylic acid groups are the longest and those which are most nearly eclipsed are the shortest in the cubane skeleton. In all cases it is the C=O rather than the C?O bond which is most nearly eclipsed with a C?C bond. The tetrahedral orientation of the substitutents does not express itself in a three dimensional supramolecular assembly; however, all four carboxylic acid groups are involved in very strong donor hydrogen bonds which result in a two dimensional array parallel to (100). An additional surprising results is the fact that none of the four substituents participate in traditional hydrogen bonded carboxylic acid dimeric moieties.     

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

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) Å, = 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) Å, 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 Å. 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 X-ray crystal structures of three bis(cyclopentadienyl)titanium(IV) derivatives

The X-ray crystal structures of (aqua)bis(cyclopentadienyl)chlorotitanium(IV) trifluoromethanesulfonate, bis(aqua)bis(cyclopentadienyl)titanium(IV) bis(trifluoromethanesul-fonate) and bis(cyclopentadienyl)bis(trifluoromethanesulfonato)titanium(IV) show a pseudo-tetrahedral array of Cp ring centroids and oxygen or oxygen and chloride donors around titanium, and varied long-range packing motifs dependent on the availability of hydrogen bond acceptors within the lattice.     

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

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) Å; V = 3001.0(7)ų; and Z = 6; 9:C₁₉H₁₉N: triclinic, P-1; a = 8.427(2), b = 12.806(3), c = 15.292(3) Å, = 70.27(3), = 80.83(3), = 72.98(3)°; V = 1482.0(6) ų; 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.     

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

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 with cell dimensions a = 6.391(2), b = 7.5826(9), c = 10.828(1) Å, a = 77.58(1), = 88.18 (2), = 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) Å, = 94.300(4)°, and 3 crystallizes in the triclinic space group with cell dimensions a = 5.614(1), b = 6.867(2), c = 7.371(2) Å, = 68.89(2), = 89.00(2), = 78.90(2)°. The three structures all contain protonated amine cations which are involved in hydrogen bonding interactions with dinitramide anions.     

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

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) Å, = 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) Å, = 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) Å, = 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 Å for 1, 0.03 Å for 2 and 0.03 Å for 3.     

The crystal and molecular structures of cyclohexanone thiosemicarbazone

Cyclohexanone thiosemicarbazone (Hchtsc) crystallizes in the triclinic crystal system with space group P (No. 2) and the following unit cell parameters: a = 6.2989(2), b = 7.9730(3), and c = 9.4118(2) Å = 79.607(3), = 85.519(2), and = 73.50(2)° V = 445.60(2) ų, Z = 2. The lengths of the bonds C(1)–S, C(1)–N(1), C(1)–N(2), and N(2)–N(3) suggest electron delocalization in all four. The S atom is trans to N(3), and this E configuration is stabilized by intramolecular hydrogen bonding between N(3) and the N(1)H₂ group. Two intermolecular hydrogen bonds involving the S atom and the N(1)–H(1b) and N(2)–H(2) groups give rise to a polymeric chain of molecule pairs.     

The crystal and molecular structures of two bromo bis(N,N-dipropylthiocarbamoyl) sulfidocopper(I) complexes

The reaction of copper(I) bromide, CuBr, with the tetraalkylthiurammonosulfides R₄tms (R = ⁱPr, ⁿPr) affords the copper(I) complexes ⁱPr₄tmsCuBr (I) (C₁₄H₂₈BrCuN₂S₂, orthorhombic, Pna2₁, Z = 4, a = 12.487(2), b = 12.699(2), c = 12.742(2) Å) and ⁿPr₄tmsCuBr (II) (C₁₄H₂₈BrCuN₂S₃, monoclinic, P2₁/n, Z = 4, a = 9.092(5), b = 23.408(11), c = 10.082(7) Å, = 104.90(5)°), which exist in the solid as monomeric units featuring three-coordinate copper(I). The ligands are bidentate and coordination is completed by the bromine atoms. The configurations of the six-membered metal-ligand ring in (I) and (II) are more severely distorted than the previously reported structurally related complexes of ethyl series. The crystal structural studies are complemented and confirmed by IR and ¹H-NMR spectroscopies, as well as room temperature, magnetic, solution conductivity, and molecular weight studies.     

The crystal and molecular structure of mercury(II) bis(isopropyl)dithiophosphate, Hg[S2P(OPri)2]2, revisited: new comments about its supramolecular self-organization

The crystal structure of the title compound, Hg[S₂P(OPrⁱ)₂]₂, has been determined by single-crystal X-ray diffraction. The compound crystallizes in the centrosymmetric P2₁/c space group with a = 11.800(1), b = 8.925(2), c = 22.167(2) Å, = 94.988(7)°, and Z = 4. The same compound has been previously reported but the structure is described there in the space group C2/c. In both cases, one phosphorodithioate moiety acts as a chelating group and the other as a bridging group between neighboring mercury atoms (related to one another by the twofold screw axis), giving rise to an infinite polymer along the direction of the b axis. It turns out that in spite of the difference in space group symmetry, the structures are remarkable similar in that they are formed from infinite polymers of similar geometry. The coordination around the Hg ion shows, however, significant differences, mainly for the bridging Hg—S(4) bond length, which is 0.16 Å smaller than that previously reported.     

The crystal and molecular structure of 2-S-methylthiouracil

2-S-Methylthiouracil crystallizes in the triclinic space group P with unit cell dimensions a = 5.508(4), b = 7.175(3), c = 8.522(2) Å, = 80.83(2), = 80.43(3), = 76.86(3)°, and Z = 2. The molecule exists in the crystal in the lactam form and is essentially planar. The molecular packing consists of molecules linked in centrosymmetric hydrogen-bonded pairs. The effects of methylation and subsequent metallation on the 2-thiouracil structure are discussed.     

The crystal and molecular structure of bis(tetramethylammonium) hexamolybdate(VI)

The crystal structure of the title compound, C₈H₂₄N₂Mo₆O₁₉ was determined by single crystal X‐ray diffraction technique. The crystals are trigonals, space group P‐3c1, with a = b = 10.0176(11) Å, c = 14.089(2) Å, γ = 120°, V = 1224.4(3) Å₃, Z = 2. The structure was solved by direct methods and refined by least‐squares methods to a Final R = 0.0316 for 1114 observed reflections with I > 2σ(I). In hexamolybdate anion, six MoO₆ distorted octahedra are fused together so that they all share a common vertex. O atoms are of three types: central, terminal and bridging, bonded to six, one and two Mo atoms, respectively. The crystallographic data of the structure was deposited with the Cambridge Data Center as No. CCDC 199679. (© 2003 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)     

Synthesis and crystal structure of bis(benzimidazolium) tetrahalocobaltate(II)

The crystal structures of benzimidazolium tetrahalocobaltates (HBz)₂[CoX₄] (X = Cl and Br) have been determined. The chloride salt is triclinic, P-1, with a = 7.670(3) Å, b = 8.307(3) Å, c = 15.730(2) Å, and = 87.37(3)°, = 84.99(3)°, = 67.72(2)°. The bromide salt is monoclinic, C2/c, with a = 15.568(2) Å, b = 8.063(3) Å, c = 5.762(2) Å and = 91.36(3)°. The structures of the two salts are closely related. Both the compounds contain isolated tetrahedral CoX₄ ^2– anions and benzimidazolium cations. In the chloride salt, three chloride ions are involved in strong hydrogen bonding while only two bromide ions participate in the bromide salt. The greater deviation from the ideal tetrahedral geometry in CoBr₄ ^2– can be related to the less extensive hydrogen-bonding network compared to the chloro complex.     

The crystal structures of p-iodo-N-(p-cyanobenzylidene)aniline and p-cyano-N-(p-iodobenzylidene)aniline

The crystal structures of the isomers NC–C₆H₄–CH=N–C₆H₄–I (CN/I) and I–C₆H₄–CH=N–C₆H₄–CN (I/CN) have been determined. CN/I is triclinic, space group P1¯ with a = 7.504(3), b = 11.936(4), c = 7.304(2) Å, = 93.09(2), = 110.49(2), = 99.04(2)°, V = 601.1(3) ų, Z = 2, and D _x = 1.818(1) g cm^–3. In both compounds there are chains of molecules held together by CN···I interactions, with N···I distances of 3.15 and 3.26 Å, respectively. The chains form similar two-dimensional sheets, which, however, stack differently in the two compounds.     

The crystal and molecular structure of ammonium-bis(malonato) oxovanadium(IV) dihydrate

The title compound, (NH₄)₂[VO(C₃H₂O₄)₂]·2H₂O, crystallizes in the monoclinic space group P2₁/n, with a=7.1889(7), b=19.254(2), c=9.879(2) Å, β=108.19(1)^o, and Z=4. The VO²⁺ cation is five-fold coordinated with two malonate anions acting as bidentate ligands and a water molecule. Infrared and Raman spectra are also reported to attain a wider insight into the compound characteristics.     

The crystal and molecular structures of isoperezone, aminoperezone, and isoaminoperezone: a comparative study of their crystal packing

The crystal structures of isoperezone (1), aminoperezone (2), and isoaminoperezone (3) have been determined by single-crystal X-ray diffraction. Compound (1) yields orange crystals, orthorhombic space group P2₁2₁2₁ with unit cell dimensions a = 6.271(6), b = 30.373(7), c = 7.257(1) Å, and Z = 4; compound (2) yields purple crystals, orthorhombic space group P2₁2₁2₁ with unit cell dimensions a = 6.498(3), b = 7.500(1) c = 29.200(6) Å, and Z = 4; compound (3) yields purple crystals, monoclinic space group P2₁ with unit cell dimensions a = 7.354(1), b = 7.511(1), c = 13.283(1) Å, = 102,07(1)°, and Z = 2. The side chains in (1)–(3) are oriented out of the plane of the quinone ring at an angle of 124, 144, and 97°, respectively. The molecules in the crystal are held together by hydrogen-bonding networks and van der Waals interactions.     

Synthesis and crystal structure of bis(2-methylbenzimidazolium) tetrahalocuprate(II)

The crystal structures of 2-methylbenzimidazolium tetrahalocuprates (H2-mebz)₂[CuX₄] (X = Cl and Br) have been detemined. The chloride salt is monoclinic, P2₁/c, with a = 8.540(2) Å, b = 16.591(2) Å, c = 14.303(3) Å, and = 98.69(2)°. The bromide salt is also monoclinic, P2₁/c, with a = 8.316(3) Å, b = 17.436(3) Å, c = 14.747(3) Å, and = 98.82(3)°. Both the compounds contain discrete distorted tetrahedral CuX₄ ^2– anions and almost planar 2-methylbenzimidazolium cations. In the chloride salt, three chloride ions are involved in hydrogen bonding instead of two bromide ions in the bromide salt.     

The crystal and molecular structures of rac-threo-ifenprodil and two other 4-benzylpiperidinyl derivatives

The crystal structures of threo-ifenprodil [threo-2-(4-benzyl-piperidin-1-yl)-1-(4-hydroxyphenyl)-propan-1-ol] (1), potent NMDA receptor antagonist, and two related, biologically active compounds: threo-2-(4-benzyl-piperidin-1-yl)-1-(4-fluorophenyl)-propan-1-ol (2) and 4-benzyl-1-phenethyl-piperidinium chloride (3) have been determined by X-ray structure analysis of single crystals. Compound 1 crystallizes in an orthorhombic system, with a space group Pna2₁ (a = 34.843(3) Å, b = 6.0261(13) Å, c = 8.9343(9) Å), compound 2 – in a monoclinic space group P2₁/c (a = 14.194(1) Å, b = 6.2831(6) Å, c = 20.948(1) Å, = 101.762(6)), and compound 3 – in an orthorhombic space group Pbca (a = 10.4627(8) Å, b = 11.2166(6) Å, c = 31.669(2) Å). The piperidine rings are close to ideal chair conformations, the substituents are in equatorial positions. Overall shapes of the molecules, defined by the dihedral angles between the terminal aromatic rings, are very similar in all three cases. In 1 and 3 the crystal packing is mainly determined by the hydrogen bonds, while in case of 2 – by weak van der Waals interactions. The molecules of 1 and 3 are disordered, and the disorder is caused by a rotation around the N–C bond.     

Synthesis and crystal structure of diaquatetra(5-methyl-1,2-oxazol-3-amine)iron(II) perchlorate

A new monomeric iron(II) complex of 5-methyl-1,2-oxazol-3-amine(moxa) has been synthesized and structurally characterized. Fe(II) atom is in a distorted octahedral environment with four ring N atoms of the oxazol and two water ligands. Complex molecules and uncoordinated oxazol ligands are linked together by hydrogen bonding. This complex is diamagnetic at different temperatures and no spin-crossover was observed. Magnetic susceptibility measurement was performed by Evans method in solution. IR and UV–vis spectrum of the complex was measured to investigate the solution behavior of the complex. The space group is P (No. 2), with a = 7.4137(2), b = 10.9395(3), c = 13.5284(3) Å, = 67.146(1), = 88.565(1), = 78.556(1)°, V = 989.31(4) ų, and Z = 1.     

The crystal and molecular structure of dichloro-(bis-1,2-diphenylphosphinoethane)platinum(II)

Crystals of PtCl₂(PPh₂)(CH₂)₂(PPh₂) (1), produced from attempts to prepare hydridochloroplatinum complexes, are monoclinic, space groupP2 ₁ /c, with four molecules in a unit cell of dimensionsa=11.478(3),b=13.263(2)c=16.343(3) Å, and =99.00(2)°. The structure was solved by the heavy-atom method and refined by block-diagonal least-squares calculations with anisotropicthermal parameters;R=0.048 andR=0.061 for 1843 observed reflections. The crystal structure contains discrete well-resolved molecules. The Pt atom has distorted square-planar coordination with Pt-P 2.208(6), Pt-Cl 2.355 and 2.341(6) Å distances, and Cl-Pt-Cl 90.2(2) and P-Pt-P 86.3(2)° angles.     

The crystal and molecular structure of N-(methylsulfonyl)-N-(2,6)-(dimethylphenyl)methanesulfonamide

The title compound, crystallizes in the triclinic space group witha=8.232(4),b=9.159(2),c=10.230(3)Å. =74.07(3)°, =72.50(4)°, =63.65(3)° andZ=2. The structure was solved by direct methods and refined by full matrix least squares methods toR=0.054 for 1817 observed reflections. The plane containing the nitrogen and sulfur atoms is perpendicular to the aromatic plane. One of the S–O bonds in each methanesulfonyl group is in nearly eclipsed conformation with the N–C bond.