Hydrogen bonding in 2-hydroxy((di)thio)benzoates. I. X-ray structures of 2,6-dimethylpiperidinium salts

X-ray structural data are reported for 2,6-dimethyl-piperidinium-2-hydroxybenzoate (C₁₄H₂₁NO₃, orthorhombic,P2₁2₁,2₁, (19);a=7.983(1)Å,b=12.680(2)Å,c=13.838(2)Å;Z=4;R=0.042) and for two polymorphs of 2,6-dimethylpiperidinium-2-hydroxythiobenzoate (C₁₄H₂₁NO₂S), an-form (monoclinic,P2₁/n (14);a=8.005(4)Å,b=22.150(2)Å,c=8.672(4)Å,=101.91(6)°;Z=4;R=0.059) with an intramolecular O-HS hydrogen bond, and a-form (orthorhombic,P2₁2₁2₁ (19);a=8.188(1)Å,b=14.781(2)Å,c=24.163(4)Å;Z=8;R=0.15) with an intramolecular O-HO hydrogen bond. The intra-and intermolecular hydrogen bond patterns are discussed, including the literature data of 2,6-dimethylpiperidinium-2-hydroxydithiobenzoate.     

The crystal structure of 2-(α-hydroxy-βββ-trichloroethyl)-4-methylphenol and its relevance to the condensation of chloral hydrate and parasubstituted phenols

The product formed by the condensation ofp-cresol and chloral hydrate in the presence of anhydrous potassium carbonate is shown by single crystal X-ray crystallography to be 2-(-hydroxy--trichloroethyl)-4-methylphenol and its failure to cyclize to form a 1,3-benzdioxin is explained. The title compound is monoclinic, P2₁,/c,Z=4,a=12.316(1),b=8.8668(9),c=10.275(2) Å,=107.90(1)°     

Low-temperature,high-resolution crystal structure study of tricyclo[3.3.1.13,7]decan-2-ol (adamantanol-2)

The structure of the title compound (C₁₀H₁₅OH) was determined by X-ray diffraction at liquid nitrogen temperature. The crystals are triclinic, spacegroupP¯1 witha=11.3686(5),b=11.3990(5),c=11.4353(6) Å,=82.193(4),=70.211(4) and =62.279(4)°,V _c =1233.9(1) ų,Z=6,F(000)=504,D _x =1.229 g cm^–3; MoK radiation, =0.71073 Å,(MoK)=0.7 cm^–1. FinalR factor=0.046 andwR=0.062 for 8162 reflections withI>2.5(I). The asymmetric unit consists of three independent adamantanol-2 molecules which together with the three symmetry-related molecules form a cluster having pseudo ¯3 symmetry. The six molecules in the cluster are connected by six O-HO hydrogen bonds, the oxygens of which constitute an almost ideal chair conformation.     

Structural characterization and photophysical properties of a luminescent trinuclear zinc(II) complex exhibiting multiple coordination geometries

A luminescent trinuclear zinc(II) complex, tris(-2,3-toluenedithiolato)-1:2²S¹;1:2²S¹, 2:3²S²;3S², 1:3²S³;3S³-bis(2,2-bypyridine)-1²N,N,2²N,N-trizinc, containing 3,4-dimercaptotoluene (tdt) and 2,2-bipyridine (bpy) has been synthesized and found to have the trinuclear formulation Zn₃(tdt)₃(bpy)₂ (I). The complex crystallizes in the monoclinic space group P2₁/n with a = 11.7247(12), b = 20.134(2), c = 17.7376(18) Å and = 103.743(2). The complex has two heteroleptic zinc(II) centers exhibiting similar distorted trigonal bipyramidal geometries with the third homoleptic zinc(II) center displaying a flattened tetrahedral geometry. Present in the solid state are both intra- and intermolecular – interactions. The complex is emissive at 77 K in the solid state with an emission maximum at 574± 2 nm with a luminescence lifetime of 7.4± 0.4 ns. The unstructured emission is assigned as a metal-mediated ligand-to-ligand –^* charge transfer transition.     

Reaction of trimethylaluminum and trimethylgallium with bifunctional amines: Syntheses and molecular structures of [Me2Al−N(CH2CH2)2−C−(OCH2)2]2 and [Me2Ga−N(Si(H)Me2)2]2

The crystalline products [Me₂Al–N(CH₂CH₂)₂–C–(OCH₂)₂]₂ (I) and [Me₂Ga–N(Si(H)Me₂)₂]₂ (II) were prepared from reactions of trimethylaluminum and trimethylgallium with 1,4-dioxa-8-azaspiro[4.5]-decane and 1,1,3,3-tetramethyldisilazane, respectively, in toluene. The organoaluminum dimer crystallizes in the monoclinic space groupP2₁/c with unit cell parametersa=8.970(2) ,b=9.683(2) ,c=12.833(3) , =103.18(2)°,V=1085.3(3) ³, andD _calcd=1.22 g cm^–3 forZ=2. Least-squares refinement based on 935 observed reflectionsI>3(I) in the range 3.5°<2<45.0° led to a finalR factor of 0.033 (R _w =0.041). The dimeric organosilazagallium crystallizes in the triclinic space group with unit cell parametersa=7.636(2) ,b=9.168(2) ,c=9.466(3), =72.81(2)°, =87.94(2)°, =69.90(2)°,V=593.0(3) ³, andD _calcd=1.30 g cm^–3 forZ=1. Least-squares refinement based on 1661 observed reflectionsI>3(I) in the range 3.5°<2<48.0° led to a finalR factor of 0.055 (R _w =0.070). Both compoundsI andII reside about a crystallographic center of symmetry and contain a planar M₂N₂ (M=Al forI, Ga forII) four-membered ring withI having an Al...Al contact of 2.801 .     

Hydrogen-bond networks in the mono- and diprotonated cyclic diamine [9]aneN2S

The hydrogen-bond networks in the mono- and diprotonated cyclic diamine, 1-thia-4,7-diazacyclononane, [9]aneN₂S, have been examined. Crystals of the monoprotonated, form [9]aneN₂S HCl, contain a ribbon-like network of alternating strong and weak intermolecular N H Cl hydrogen bonds and weak intramolecular N H N hydrogen bonds. Crystal data for [9]aneN₂S HCl: monoclinic, a = 6.6640(6) Å, b = 10.3493(9) Å, c = 6.9807(6) Å, = 108.847(1)°, V = 455.63(7) ų, space group P2₁, Z = 2. In the di-protonated form, [9]aneN₂S 2HBr, the ribbon-like network comprises strong intermolecular and weak intramolecular N H Br hydrogen bonds. Crystal data for [9]aneN₂S 2HBr: orthorhombic, a = 12.5918(13) Å, b = 8.0753(9) Å, c = 10.6856(11) Å, V = 1086.5(2) ų, space group Pnma, Z = 4. The chloride anions of [9]aneN₂S HCl align in interlocking columns in the a- and c-direction whereas the bromide anions in [9]aneN₂S 2HBr occupy channels in the b-direction.     

Crystal and molecular structure of 3-(4-chlorobenzoylimino)-5,6-dihydro-3H-imidazo[2,1-c]-1,2,4-dithiazole

Crystal structure of the title compound belonging to the group of-acylimino derivatives of sulfur(II) compounds has been determined by X-ray structure analysis. The crystals are monoclinic, P2₁/c,a=11.210(2),b=8.197(1),c=13.659(2) Å,=102.36(2)°,V=1226.0(3) ų,Z=4,D _x =1.61 g cm^–3, (MoK)=0.71069 Å,=6.3 cm^–1. The structure has been refined to a finalR value of 0.035 for 1401 observed reflexions.The molecule is nearly planar with symmetrym. The title compound contains a very short intramolecular C=OS contact of 2.328(3) Å, suggesting a bond-non-bond resonance interaction.     

Conformational analysis and X-ray structure of 1-(2,4-dichlorobenzyl)-1H-indazole-3-carboxylic acid

The results of a X-ray structure determination and of a quantum-chemical Conformational analysis on the title compound are reported. The crystals belong to the triclinic system, space groupP¯1 (after structure determination), with two molecules in the unit cell, whose parameters are:a=11.966(2),b=8.118(2),c=7.693(2)Å,=97.03(2),=92.98(2), =106.15(2)°: observed density (by flotation) 1.49, calculated 1.503 g cm^–3. The structure was solved from 1815 diffractometer-measured intensities, withI2.5(I) and refined by full-matrix least-squares to a final conventional indexR=0.035 (R _w =0.043). The most relevant feature of the molecular structure is the orientation of the dichlorophenyl ring with respect to the planar indazole group, the dihedral angle being 83.1(1)°. A very close conformation corresponds to one of the minima calculated by the semiempirical AMI method.     

Anticancer agent development. 5. X-ray structure and1H nmr spectral analysis of (1α,2α,5α,6α)-2,6-bis(3,4-methylenedioxyphenyl)-3,7-dioxabicyclo[3.3.0]octane-4,8-dione

The title compound, C₂₀H₁₄O₈, Mr=382.3, crystallized from chloroform in the centric space group P¯1 witha=6.516(4),b=6.798(3),c=9.545(7) Å,=85.31(5),=73.87(5), =79.59(4)°,V=399.2 ų, and D_calc=1.59 g cm^–3 forZ=1. Least-squares refinement of 1035 observed [F_o5(F_o)] reflections led to the final agreement index ofR=0.074. The molecule resides on a crystallographic center of inversion and is disordered into two different conformations. This manifests itself as a 50/50 disorder at O(4), C(2), and C(3). The observed structure reveals acis relationship between the bridgehead hydrogen atoms and the aryl rings. The 90 MHz¹H nmr spectrum of the title compound exhibits an AAXX spin system with a H(1)C(2) to H(1)C(3) and H(1)C(2) to H(1)C(3) coupling constant of 2.8 Hz. Computer spectral simulation and Karplus equation analysis are utilized to illustrate a relaxation of the torsion angles between H(1)C(2) and H(1)C(3), and H(1)C(2) and H(1)C(3) is solution.     

Crystal and molecular structure of 3-phenylisoxazolin-4,5-dione-4-[3′-phenyl-(2′H)Δ3′-isoxazolin-5′-on-4′-yl]hydrazone

The crystal and molecular structure of 3-phenylisoxazolin-4,5-dione-4-[3-phenyl-(2H)³-isoxazolin-5-on-4-yl]hydrazone, C₁₈H₁₂N₄O₄, has been determined from X-ray diffractometer data and refined by least-squares methods toR=0.047 for 1413 observed reflections. Crystals of C₁₈H₁₂N₄O₄ are monoclinic:a=13.76(1),b=11.11(1),c=14.10(1) Å, =90.5(1) °,Z=8, space groupC2/c.Among 11 possible tautomeric structures, this compound exhibits a hydrazono structure with intermolecular hydrogen bonds. The phenyl rings make angles of 9.03 ° and 35.12 ° with the planes of the isoxazole rings. Bond distances and angles have reasonable values, and extensive conjugation is evident within the molecule. Close molecular packing is given by layers of molecules approximately parallel to the (001) plane, and in each layer rows of molecules joined by hydrogen bonds run parallel to (¯110).     

The chemistry of the “insoluble red woods.” Part 15. The crystal structures of 7-benzyloxy-6,2′,3′,4′-tetramethoxy- and 2,6,7,2′,3′,4′-hexamethoxy-isoflav-3-ene

The reaction of 7-benzyloxy-6,2,3,4-tetramethoxyisoflavylium perchlorate with 1-(2,4-dimethoxyphenyl)-3-(3,4-dimethoxyphenyl)-prop-l-ene and of 6,7,2,3,4-pentamethoxyisoflavylium perchlorate with the same propene yielded respectively 7-benzyloxy-6,2,3,4-tetramethoxyisoflav-3-ene (5) and 2,6,7,2,3,4-hexamethoxyisoflav-3-ene (7) whose structures have been established by X-ray crystallography. Crystals of (5) are monoclinic, space groupP2₁/a (No. 14) with four molecules in a unit cell of dimensionsa=8.528(2),b=13.294(3),c=19.629(4) Å,=99.92(2)°. Crystals of (7) are also monoclinic, space groupC2/c (No. 15) with eight molecules in a unit cell of dimensionsa=28.088(3),b=10.662(3),c=12.869(1) Å,=97.32(1)°. Both structures were solved by direct methods and refined by full-matrix least-squares calculations to finalR values of 0.053 and 0.041 for 1673 and 1424 observed data for (5) and (7) respectively. The molecular dimensions are in accord with accepted values.For Part 14 see Whalley, W. B., Ferguson, G., and Khan, M. A., (1980)J. Chem. Res. (M), 2219.     

Crystal and molecular structure of 3-methoxy-6-nor-6,7-secooestra-1,3,5(10),9(11), 14-penten-17-one-8β-ethyl carboxylate

C₂₀H₂₂O₄,M _r =326.39, triclinic,P¯1,a=10.365(2),b=11.383(2),c=8.461(1) Å, =103.60(1),=104.44(1), =105.23(1)°,Z=2, (CuK)=1.54178 Å;R=0.0633 for 1940 reflections. The results of the X-ray analysis have shown that the ethyl carboxylate substituent is oriented. The geometry of the main skeleton of the molecule has not revealed any significant differences in the present compound and in the case of the epimeric molecule.     

Crystal structures of 1-(2-hydroxyphenyl)-3-phenyl-1,3-propanedione and 1-(1,3-benzodioxol-5-yl)-3-(2,4-dimethoxyphenyl)-1,3-propanedione

1-(2-Hydroxyphenyl)-3-phenyl-1,3-propanedione crystallizes in the triclinic space group (a=5.4233(5),b=13.910(1),c=17.036(1) Å, =68.311(6), =80.854(7), =78.760(8)°) as two independent enolic tautomers in which the hydroxyl and phenolic protons are hydrogen bonded to the ketonic oxygen atom. The structure was refined toR=0.039 for 2085I3(I) reflections. 1-(1,3-Benzodioxol-5-yl)-3-(2,4-dimethoxyphenyl)-1,3-propanedione, which belongs to the triclinic space group (a=7.3990(7),b=8.1239(5),c=14.004(1) Å, =86.673(6). =88.574(7), =64.885(7)°) also exists in the enolic form. The structure was refined toR=0.040 for 1564I3(I) reflections.     

On the organoaluminum chemistry of multidentate phosphine ligands. Reaction of trimethylaluminum with bis(diphenylphosphino)methane: Synthesis and molecular structure of [Al(CH3)3]2[(C6H5)2PCH2P(C6H5)2]

Reaction of an excess of trimethylaluminum with bis(diphenylphosphino)-methane in heptane affords the crystalline complex [A1(CH₃)₃]₂[(C₆H₅)₂PCH₂P(C₆H₅)₂]. The title compound crystallizes in the triclinic space group P¯1 with unit cell parametersa=10.053(6),b=11.017(6),c=15.908(8) Å,=85.58(4),=71.80(4), =77.49(4)°,V=1634(1) ų, andD _c=1.07 g cm^–3 forZ=2. Least-squares refinement based on 2924 observed reflection with intensitiesI3I) in the range 2.00245.0° converged atR=0.050 (R _w=0.067). The Al-P distances are 2.585(2) and 2.521(2) Å, and the P-C-P angle is 121.4(2)°.     

Refinement of the crystal structure of malonic acid,C3H4O4

A reinvestigation of the X-ray crystal structure of malonic acid (C₃H₄O₄) has been made in the light of some observations arising from solid-state¹³C NMR studies on this compound. The unit cell parameters are:a=5.156(1),b=5.341(1),c=8.407(1) Å, =71.48^o (2), =76.12^o (2), =85.09^o (2), space group ,Z=2. The structure was solved by direct methods and refined by full-matrix least-squares refinement to a finalR value of 0.038 for 711 unique reflections withl>3. The packing of the molecules involves dimeric hydrogen bonded association of each carboxyl group with a centrosymmetrically related neighbor. The angles O–C–O (123.3^o and 124.8^o, respectively) for the two carboxyl groups agree qualitatively with the values predicted from a linear relationship relating the observed ₂₂ component of the Carbon-13 NMR chemical shielding tensor for the carboxyl carbon atom to the bond angle O–C–O at the carbon atom.Contribution No. 825.     

The crystal structure of 2-nitroresorcinol

2-Nitroresorcinol is triclinic, space group P; at –100°Ca=7.083(2),b=7.696(2),c=6.607(2) Å, =74.61(2), =77.81(2), =68.64(2)°,V=320.8(2) ų,D _x=1.606(1) g cm^–3,Z=2. The two hydroxyl groups form symmetric intramolecular hydrogen bonds to the nitro group. The molecules pack in stacks held together by - interaction with adjacent molecules in a head-to-tail arrangement.     

A comparison of the coordination preferences of Zn, Co, and Cd(II) with the heteroscorpionate ligand (2-hydroxy-3-t-butyl-methylphenyl)bis (3,5-dimethylpyrazolyl)methane

Reaction of the Zn, Cd, or Co nitrate salts with the deprotonated ligand (2-hydroxy-3-t-butyl-methylphenyl)bis(3,5-dimethylpyrazolyl)methane (L1O^–) in methanol produced the following complexes: [(L1OH)Zn(NO₃)₂] in two isomorphs, a = 40.983(8) Å, b = 9.571(2) Å, c = 15.667(8) Å, = 90, = 106.38(1), = 90, C2/c, and a = 13.027(3) Å, b = 14.781(4) Å, c = 16.107(3) Å, = 90, = 105.30(1), = 90, P2₁/n; [(L1OH)Cd(pz)(NO₃)₂] a = 14.7476(2) Å, b = 13.5411(2) Å, c = 16.7223(2) Å, = 90, = 110.3840(10), = 90, P2₁/c; and [(L1O)Co(pz)(NO₃)] a = 11.4240(2) Å, b = 13.4498(2) Å, c = 13.8056(2) Å, = 105.2080(10), = 105.8130(10), = 112.7470(10), P . The Zn adopts a pseudotetrahedral four-coordinate geometry where the potentially tridentate ligand is actually bidentate with a protonated and uncoordinated phenoxy arm. The Co complex is pseudooctahedral six-coordinate where the phenoxy arm is deprotonated and coordinated. Finally the Cd complex is seven-coordinate but the metal is not coordinated through the phenoxy group that is again protonated.     

The crystal structure of a cyclodecabis[1,2,3]selenadiazole

4,5,6,10,11,12-hexahydrocyclodeca[1,2-d6,7-d]bis[1,2,3]selenadiazole, C₁₀H₁₂N₄Se₂, crystallizes in triclinic space group P witha=5.4625(3),b=7.2091(4),c=8.3122(6) , =65.313(5), =77.476(5), =77.442(5)°,V=287.35(4) ³,Z=1. The structure was refined toR=0.031 andR _w=0.030 for 2018 observed reflections. The molecule lies on an inversion center. The cyclodecadiene ring adopts an elongated chair conformation. The near-zero torsion angle of the elongated chair lies at the ring-fusion bonds, with a magnitude of 2.9(3)°. The five atoms of the selenadiazole ring exhibit maximum deviation 0.005(2) from planarity, with the adjacent carbon atoms lying respectively 0.020(2) and 0.059(2) to the same side of this plane. The torsion angles about the bonds comprising the sides of the elongated chair vary in magnitude from 61.0(2)° to 55.7(2)°. The cyclodecadiene C=C bond lengths are 1.368(2) . The selenium-carbon bond length is 1.850(2) . The Se–N distance is quite long, 1.888(2) .     

Crystal and molecular structure of OC(CoC5H5)3(CF3CCCF3)

The structure of the title compound has been confirmed by an X-ray diffraction analysis, and refined by full-matrix least squares. The crystals are mono-clinic:a=9.171(3),b=25.176(15)c=9.192(3) Å,=117.08(3)°,Z=4,D _x =1.976g cm^–3,=2.66mm^¯1, space groupP2₁/n (No. 14). The finalR value is 5.7%. Interatomic distances and bond angles are compared with those reported in related molecules.The preferred name of this compound according to the IUPAC rules is ₃-[11–2-bis(trifluoromethyl)vinylene]- ₃-carbonyl-tris (-cyclopentadienyl)-triangulo-tricobalt.     

Synthesis and structure of 4-R,5-R-[5-(hydroxy-diphenyl-methyl)-2, 2-dimethyl-[1,3]dioxolan-4-yl]-phenyl-methanone, a chiral ligand building block

A triphenyl analog of taddol, 4-R,5-R-[5-(hydroxy-diphenyl-methyl)-2,2-dimethyl-[1,3]dioxolan-4-yl]-phenyl-methanone, has been synthesized and structurally characterized. This molecule could act as a chiral ligand building block in the creation of tuned taddol analogs. Structural analysis of the title compound reveals that the hydroxyl group is involved in an intramolecular hydrogen bond and does not take part in any intermolecular interaction. Crystal packing is influenced by C–H O hydrogen bonding and phenyl phenyl interactions. Crystal data: Triclinic, P1 (No. 1), a = 5.9343(4) Å, b = 8.2367(17) Å, c = 10.987(2) Å, = 88.290(6), = 75.442(4), = 80.655(6), V = 512.86(15) ų, Z = 1, D _calc = 1.258 mg/m³. Final residual values were R ₁ = 0.0407 for 3022 observed data (I > 2s(I) ) and wR ₂ = 0.0941 for all 3524 unique data.