Synthesis and X-ray structure of 3-(4-methyl phenyl)-2-(4-biphenyl)-1,3-thiazolidin-4-one

The title compound (C₂₂H₁₉NOS) was synthesized, characterized and structure was determined by X-ray diffraction method. It crystallizes in the monoclinic space group P2₁/c with cell parameters a = 22.181(2) Å, b = 6.0760(4) Å, c = 13.349(3) Å, = 95.615(3)^, and {Z = 4}. The final residual factor is 0.0625 for 1724 reflections with I > 2(I). 4-thiazolidinone ring moiety shows twisted conformation.     

Synthesis and X-ray crystal structure studies of 1-ethyl-3-(2-chlorophenyl)-1,2,3-triazolium perchlorate

The isolation of stable carbenes of the Arduengo (1a) and Wanzlick (2a) type has prompted us to look for stable nitrenium ions of the related structural type 1-ethyl-3-(2-chloropenyl)-1,2,3-triazolium perchlorate (6⁺ClO₄ ^–). The title compound was synthesized and the structure was investigated by X-ray crystallography. It crystallizes in the monoclinic space group P2 ₁/n with cell parameters a = 7.066(4) Å, b = 27.680(6) Å, c = 7.486(2) Å, = 111.22(3)°, and Z = 4. The structure exhibits arrangement of the molecules with intermolecular hydrogen bonds within the layers.     

Synthesis,characterization, and crystal structure analysis of 2-(2-hydroxy-3-methoxyphenyl)-1-(4-chlorophenyl)-4,5-diphenyl-1h-imidazole

The substituted imidazole C₂₈H₂₁ClN₂O₂, was prepared via multicomponent reactions and the product crystallized using dimethylformamide. The structure of the compound was established by elemental analysis, Fourier transform infrared spectroscopy, thermogravimetric analysis, UV-visible, proton nuclear magnetic resonance spectroscopy, and single-crystal X-ray diffraction. The molecule is crystallized in the tetragonal crystal system with the space group P4₃2₁2 and with unit cell parameters a = 12.246(4) Å, b = 12.246(4) Å, c = 31.781(2) Å, and Z = 8. The molecular and crystal structures of the title molecule are stabilized by the intramolecular interactions, O-H···N and C-H···N, and intermolecular interaction, C-H···O.     

Synthesis and crystal structure of 3-[2-oxo-2-(4-methyloxyphenylsulfonamidophenyl)ethylidene]-3,4-dihydro-1H-quinoxalin-2-one

3-[2-Oxo-2-(4-methyloxyphenylsulfonamidophenyl)ethylidene]-3,4-dihydro-1H-quinox-alin-2-one (4) was synthesized and characterized by ¹H NMR,¹³C NMR, IR, and single-crystal X-ray diffraction techniques. The crystallographic results show that the composition of the title compound is C₂₃H₁₉N₃O₅S. It belongs to triclinic crystal system and P-1 space group, with a=7.273(6) ?, b=9.092(7) ?, c=15.928(13) ?; α=85.135(11)°, β=78.297(10)°, γ=84.619(11)°, V=1024.4(14) ?³, Z=2, D _c=1.457 mg/m³, μ = 0.201 mm⁻¹, F(000)=468, R=0.0597, wR=0.1438. Supplementary material CCDC-281953 contains the supplementary crystallographic data for this paper. These data can be obtained free of charge at www.ccdc.cam.ac.uk/retrieving.html or from the Cambridge Crystallographic Data Centre, 12 Union Road, Cambridge CB2 1EZ, UK; fax: +44-1223-336033; e-mail: deposit@ccdc.cam.ac.uk.     

PM3 semiempirical study and its comparison with X-ray crystal structure of 4-[2-Methyl-4-(4-methoxyphenylazo)] phenoxyphtalonitrile

  The molecular and crystal structures of the title compound, C₂₂H₁₆N₄O₂, were determined by single crystal X-ray diffraction technique. The title compound crystallizes in monoclinic space group P1 2 ₁ /n1, with a=12.7811(9) ?, b=8.2002(4) ?, c=17.8772(14) ?, Z=4, D _calc=1.3112(1) g/cm³, μ (Mo-K_α)=0.087 mm⁻¹. The structure was solved by direct methods and refined to a final R=0.056 for 1891 reflections with I > 2σ (I). The asymmetric unit in the crystal structure contains only one neutral molecule. The positions of nitrogen atoms in the azo groups were disordered. There is no classic hydrogen bond in the crystal structure. The molecules in the crystal structure are stacked by π–π stacking and one edge-to-face interactions. In order to determine conformational flexibility and crystal packing effects on the molecules, molecular energy profile of the title compound was obtained with respect to the selected torsion angle, which is varied from −180° to +180° in every 10° via PM3 semi-empirical method.     

Synthesis and Crystal Structures of (E)-1-Phenyl-3-[(2,4,6-Trimethylphenyl)]prop-2-En-1-One and (E)-1-Phenyl-3-[(4-Trifluoromethylphenyl)]prop-2-En-1-One

Two chalcone compounds, namely (E)-1-phenyl-3-[(2,4,6-trimethylphenyl)]prop-2-en-1-one (1) and (E)-1-phenyl-3-[(4-trifluoromethylphenyl)]prop-2-en-1-one (2), have been synthesized and structurally characterized by elemental analysis, ¹H NMR spectrum, and single-crystal X-ray diffraction analysis. The chalcone molecules in (1) and (2) have the common skeleton of 1,3-diaryl-2-propen-1-one and adopt an (E)-configuration about the C = C double bonds. In addition, X-ray analysis reveals that the π···π stacking interactions are well observed in the crystal structure of (1) and (2).     

Intramolecular hydrogen bonding and tautomerism in N-(3-pyridil)-2-oxo-1-naphthylidenemethylamine

N-(3-pyridil)-2-oxo-1-naphthylidenemethylamine (C₁₆H₁₂N₂O) was studied by elemental analysis, IR, ¹H NMR, and UV–visible techniques and X-ray diffraction methods. The UV–visible spectrum of the compound was investigated in solutions effect polarity. The polarity of the some solvents was modifierly the additional (CF₃COOH) and [(C₂H₅)₃N]. The compound is in tautomeric equilibrium (phenol-imine O–H···N and keto-amine O···H–N forms) in polar and nonpolar solvents. The keto-amine form is observed in basic solutions of DMSO, ethanol, chloroform, benzene, cyclohexane, and in acidic solutions of chloroform and benzene, but not in acidic solutions of DMSO and ethanol. The compound crystallizes in the monoclinic, space group P2₁/a with a = 7.010(5) Å, b = 13.669(4) Å, c = 12.764(4) Å, = 101.23(4)°, V = 1199.6(10) ų, Z = 4, D _c = 1.375 g/cm³, (Mo K) = 0.088 mm^–1, R = 0.045 for 1658 reflections [I > 2(I)]. The title compound is not planar two Schiff base moieties A [C1–C11, O1] and B [N1, C12, C13, N2, C14, C15, C16] are inclined at an angle of 27.4(1)° reflecting mainly the twist about C12–N1 [C11–C12–N1–C13, 29.7(2)°]. There is a strong intramolecular hydrogen bond (O–H···N) of 2.529(2) Å.     

Intramolecular hydrogen bonding and tautomerism in 1-[N-(4-bromophenyl)]aminomethylidene-2(1H) naphthalenone

1-[N-(4-bromophenyl)]aminomethylidene-2(1H)naphthalenone (C₁₇H₁₂NOBr) (1) was synthesized and its crystal structure was determined. Compound (1) is monoclinic, space group P2₁/n with a = 4.808(1) Å, b = 20.617(1) Å, c = 13.750(1) Å, = 93.004(1)°, V = 1361.11(3) ų, Z = 4, D_c = 1.592 g·cm^–3, (Mo K) = 3.014 mm^–1, R = 0.051 for 1013 reflections [I > 2(I)]. There is a strong intramolecular hydrogen bond of distance 2.544(2) Å between the hydroxyl oxygen atom and imine nitrogen atom, the hydrogen atom essentially being bonded to the nitrogen atom. The title molecule is not planar. X-ray crystal structure determination reveals the existence of the keto (or predominantly keto) tautomer in (1). Spectra of compound (1) were observed by IR and NMR, and UV–visible spectra of (1) were studied in different solvents and acidic media.     

Crystal structure of the piperazine-1,4-diium (DL-)hydrogen malate (1:2)

The crystalline salt of piperazine-1,4-diium (DL-)hydrogen malate (1:2), (C₄H₁₂N₂)²⁺ (C₄H₅O₅)₂^–, has been prepared and characterized by X-ray crystallography. The title salt crystallizes in monoclinic space group P2₁/n with a = 7.073(1), b = 14.180(2), c = 7.526(1) Å, = 94.66(1), V = 752.33(18) ų and Z = 2. Results indicate that the title salt exists as a racemic compound but a conglomerate. In the structure, axial and equatorial hydrogen atoms of piperiaine-1,4-diium are all involved in different bifurcated hydrogen bonds. The integral structure, formed by the hard hydrogen bonds of N–HsO and O–HsO, is stabilized further by soft hydrogen bond of C–HsO.     

Structural studies of a novel bioactive benzophenone derivative: (4-Chloro-2-hydroxy-phenyl)-phenyl-methanone

The title compound (4-Chloro-2-hydroxy-phenyl)-phenyl-methanone was synthesized and the product obtained was characterized by spectroscopic techniques, and finally the structure was confirmed by X-ray diffraction studies. The compound crystallizes in the orthorhombic crystal system with the space group Pbca with unit cell parameters, a = 14.0359(5) Å, b = 6.8084(3) Å, c = 23.1097(8) Å, and Z = 4. The structure exhibits an intramolecular hydrogen bond which closes an S(6) ring. No directional interactions beyond the van der Waals packing contacts were identified in the crystal structure.     

4-(1,4-Dimethoxy-2-naphthyl)-4- hydroxycyclohexanone and its ethylene ketal

Intramolecular hydrogen bonding in the solid state is reported for the title compound and its ethylene ketal. The title compound crystallizes in the triclinic space group, with a = 9.590(3), b = 9.620(3), c = 9.844(2) Å, = 97.67(2), = 105.25(2), = 115.47(2), and Z=2. The ethylene ketal crystallizes in the monoclinic space group, P2₁/c, with a = 7.230(2), b = 22.639(3), c = 10.839(2) Å, = 101.47(2), and Z = 4. The intramolecular hydrogen bond length of 1.79 Å is the same for the ketone and ketal, but the O—H---O valence angle is 144° for the ketone and 165° for the ketal.     

Crystal structures of 3-[1-Benzenesulfonyl-3-phenylsulfanyl-1H-indol-2-yl]-1-[4-(methyl (I)/methoxy (II) phenyl)]-2-phenyl-propane-1-one

The compounds 3-(1-Benzenesulfonyl-3-phenylsulfanyl-1H-indol-2-yl)-1-[4-methyl (I)/methoxy (II)phenyl)]-2-phenyl-propane-1-one crystallize in triclinic space group P . The details are: compound I a = 11.941(6) ?, b = 12.154(7) ?, c = 13.006(7) ?, α = 63.124(8)°, β = 84.464(9)°, γ = 64.810(8)°, V = 1519.7(14) ?³, Z = 2, D _cal = 1.284 Mg m⁻³, and R = 0.0382 (wR = 0.0978); compound II a = 11.897(6) ?, b = 12.268(6) ?, c = 13.001(7) ?, α = 61.919(8)°, β = 83.480(8)°, γ = 64.676(7)°, V = 1504.0(14) ?³, Z = 2, D _cal = 1.333 Mg m⁻³, and R = 0.0422 (wR = 0.1049). The indole ring system in both the molecules I and II are not strictly planar and the dihedral angles formed by the pyrrole and benzo planes are 4.0(7)° and 3.5(8)°, respectively. The C–HO, C–Hπ and ππ types of interactions stabilize the molecules in the unit cell in addition to van der Waal's forces in I and II.     

Crystal and molecular structure studies of 2-(3-chlorophenyl),3,5-diphenylisoxazolidine

The structure of the title compound, 2-(3-chlorophenyl),3,5-diphenylisoxazolidine (C₂₁H₁₈ NOCl) (1) has been investigated by X-ray crystallography. Compound (1) crystallizes in orthorhombic space group P2₁2₁2₁ with cell parameters a=10.288(17) Å, b=37.98(3) Å, c=8.809(9) Å, Z=8. Compound (1) has both intra- and intermolecular hydrogen bonds.     

Analysis of the configuration and hydrogen-bonding interactions in the crystal structure of 5,8-dimethoxy-2,3-bis(2-pyridinio)quinoxaline perchlorate dihydrate

The perchlorate salt of diprotonated 5,8-dimethoxy-2,3-bis(2-pyridyl)quinoxaline, [C₂₀H₁₈N₄O₂]·(ClO₄)₂ ·(H₂O)₂ (1), has been prepared and characterized by ¹H NMR, IR, UV–Vis, and elemental analysis, and established by X-ray diffraction technique. In the crystal structure of the title compound, two pyridinio rings form dihedral angles of 38.7(6)° and 26.5(5)° with the mean quinoxaline plane, and a dihedral angle of 52.7(6)° with each other. It is unexpected that the favorite orientation of two protonated pyridyl rings is such that their nitrogen donors are opposite to each other (trans–trans configuration). The most striking feature of this structure resides in the fact that numerous hydrogen-bonding interactions are observed, resulting in a novel double-chain supramolecular architecture along crystallographic [111] direction. There exist significant face-to-face – stacking interactions between the interchain neighboring pyridinio rings, which may further stabilize this structure.     

Structure of (Z)-1-p-methoxyphenyltelluro-1,4-diphenyl but-1-en-3-yne

C₂₃H₁₈TeO,M _r=437.97, ,a=9.940(2),b=13.664(3),c=7.895(2) Å, =80.60(1), =69.71(2), =75.95(1)°,V=972.0(4) ų,Z=2,R=0.041 for 2668 observed reflections. The Te–C bond distances are 2.109(5)Å and the C–Te–C angle is 96.0(2)°. The phenyl rings are planar to within experimental accuracy, making dihedral angles of 64.6(2), 65.3(2) and 31.1(3)°.     

Methyl 4-((E)-2-{3-[(3-{ (E)-2-[4-(methoxycarbonyl)phenyl]- 1-diazenyl}-5,5-dimethylhexahydro-1-pyrimidinyl)methyl]-5,5-dimethylhexahydro-1-pyrimidinyl-1-diazenyl) benzoate. X-ray crystal structure

Methyl 4-((E)-2-{3-[(3-{(E)-2-[4-(methoxycarbonyl)phenyl]-1-diazenyl}-5, 5-dimethyl hexahydro-1-pyrimidinyl)methyl]-5, 5- dimethylhexahydro-1- pyrimidinyl}-1- diazenyl) benzoate (1) has been synthesized by reaction of a mixture of formaldehyde and 2,2-dimethyl-1,3-propanediamine with p-methoxycarbonylbenzenediazonium chloride. The crystal structure of 1 has been determined by single crystal X-ray diffraction analysis. The crystals of 1 displayed problems of disorder; the asymmetric unit is built up by two independent molecules, which display disorder within a methoxycarbonyl group. The two independent molecules in the asymmetric unit are very similar, differing only slightly about the mutual orientation of the aryltriazenyl groups. With respect to the N–C–N bridge between the hexahydropyrimidinyl rings, the two equivalent fragments containing the triazene moieties are in a cis orientation. The N–N single bonds, in the range 1.319(4)–1.348(4) Å, and the N=N double bonds, in the range 1.255(5)–1.275(4) Å, indicate significant conjugations within the triazene moieties. All the hexahydropyrimidine six-membered rings adopt a chair conformation as shown by their puckering parameters. The crystal packing is determined only by simple van der Waals interactions. The crystal structure of 1 is compared with the previously reported structure of the unbranched hexahydropyrimidine analogue 2. Crystal data: 1 C29H40N8O4, triclinic, space group P-1, a = 13.9652(2), b = 14.2908(3), c = 16.6129(4) Å, = 97.279(1), = 90.872(1), = 107.385(1), V = 3133.6(1) ų, for Z = 4.     

X-ray crystallographic analysis and NMR study of (Z)-3(2-hydroxyphenyl)-1(4-methoxyphenyl)-3-oxo-prop-1-en-1-ol

The molecular structure of the title compound has been determined by X-ray crystallography. The enol form is present in the solid state and each of the two molecules in the asymmetric unit possesses two intramolecular hydrogen bonds. The delocalization of double bonds results in an almost planar molecule. Evidence to support the enol configuration in solution is presented from an NMR investigation.     

Synthesis and crystal structure of 4,5-(cis-cyclohexylenedithio)-1,3-dithiole-2-one

The x-ray crystal structure of 4,5-(cis-cyclohexylenedithio)-1,3-dithiole-2-one has been determined. Yellow block shaped crystals of C₉H₁₀OS₄ crystallize in the space group P with cell dimensions a = 8.872(4), b = 9.330(8), c = 14.333(12) Å, = 95.23(7), = 91.09(5), = 107.60(5)°, V = 1124.8(14) ų, and Z = 4. This compound has two S---S contacts [3.574, 3.610 Å] shorter than 3.70 Å and the usual disordered ethylene moiety [C(3)—C(8)] of the six-membered ring is fixed by the cis-cyclohexylene subsitituent. This means that it may be a new precursor for conducting and strong near-IR absorbing nickel-dithiolenes. Also, it provides the first example of polymorphism of the dmit derivatives and contains two independent molecules I and II in the asymmetric unit.     

Crystal structure of [Mn2(III)(salpa)2Cl2(H2O)2] (H2salpa = 1-(salicylaldeneamino)-3-hydroxypropane)

The manganese complex, (Mn₂(III)(salpa)₂Cl₂(H₂O)₂], has been prepared and its structure determined using x-ray crystallography. The dimer is a di-₂-alkoxo complex which is a six-coordinate manganese dimer with unsupported alkoxide bridges and a rare example of a chloride- and water-containing manganese dimer. The complex crystallizes in the monoclinic space group P2₁/c with a = 9.315(5), b = 11.130(4), c = 11.637(5) Å, = 104.33(3)°, V = 1169.0(9) ų, and Z = 2. The structure comprises discrete binuclear clusters in which the metal atoms are bridged by two alkoxo oxygens of the salpa^2– ligands. The Mn—O and Mn—N distances are in good agreement with those found for other manganese(III) Schiff base complexes. The Mn—Cl and Mn—O3 distances are 2.585(2) and 2.371(2) Å, respectively, and the Mn ··· Mn distance is 3.001(1) Å. In the crystal, there are two types of hydrogen bonding between the H₂O molecule and the Cl atom with Cl ··· H(H₂O) distance of 2.33(6) (intramolecule: –1 + x, y, –1 + z) and 2.68(6) Å (intermolecule: –1 + x, 0.5–y, –0.5 + z).     

Crystal and molecular structure of di(1-pyrazolyl)methane,CH2(C3N2H3)2

The title compound consists of two planar pyrazolyl fragments oriented at 73.0° to each other and linked to a common carbon atom. All hydrogen atoms were located unambiguously and their positions were refined.