Crystal Structure and Molecular Conformational Studies of Allyl 6-Amino-5-cyano-4-(4-fluorophenyl)-2-methyl-4H-pyran-3-carboxylate

Crystallography Reports - The allyl 6-amino-5-cyano-4-(4-fluorophenyl)-2-methyl-4H-pyran-3-carboxylate, C17H15FN2O3, compound adopts a triclinic crystal system with the sp. gr. $$P\bar {1}$$, Z =...     

Crystal and molecular structure of 6,7-benzo-3,4 (1,4-dimethoxy-2,3-naphtho)-1,5-dioxosuberane

The crystal and molecular structure of the title compound (2) C₂₁H₁₆O₄ has been determined by an X-ray analysis, by direct methods from diffractometer data and refined by full-matrix least squares. The compound (2) crystallizes in the space group P2₁/a, with cell parameters:a=36.432(5),b=5.512(3),c=8.269(5) Å, =108.0(3)°,z=4,D _c =1.397 g/cm^–3,R=7.8 for 1136 observed reflections. The conformation of the tetracyclic ring system shows a folding of two planar parts of the carbon skeleton about an axis passing thorough C8 and C16 of the seven membered ring C.     

Crystal Structure of Ethyl 6-Amino-5-cyano-4-(4-fluorophenyl)- 2,4-dihydropyrano[2,3-<Emphasis Type="Italic">c</Emphasis>]pyrazole-3-carboxylate

Ethyl 6-amino-5-cyano-4-(4-fluorophenyl)-2,4-dihydropyrano[2,3-c]pyrazole-3-carboxylate was synthesized based on a commercially available trisodium citrate dihydrate as an inexpensive and eco-friendly catalyst for the first-time via one-pot tandem Knoevenagel-cyclocondensation of malononitrile, 4-f luorobenzaldehyde and in situ generated ethyl 5-oxo-2,5-dihydro-1H-pyrazole-3-carboxylate in aqueous ethanol at room temperature and its crystal structure is determined by X-ray structure analysis. The crystals are triclinic, sp. gr. \(P\bar 1\), a = 8.7914(7) Å, b = 11.3632(8) Å, c = 11.4005(9) Å, α = 62.278(7)°, β = 71.099(7)°, γ = 80.856(6)°, Z = 2, R = 0.0544 for 2491 observed ref lections. Pyran and pyrazole rings are almost coplanar and phenyl ring is almost perpendicular to these two rings. Pyran ring adopts boat conformation. The crystal structure is stabilized by N–H···N, N–H···O, C–H···F, and C–H···π hydrogen interactions. In addition, a number of weak π···π interactions also contribute to stabilize the crystal structure.     

Synthesis,Characterization and Crystal Structure of Ethyl 2-amino-4-(4-fluorophenyl)-6-phenylcyclohexa-1,3-diene-1-carboxylate

Ethyl 2-amino-4-(4-fluorophenyl)-6-phenylcyclohexa-1,3-diene-1-carboxylate was synthesized from ethyl 6-(4-bromophenyl)-4-(4-fluorophenyl)-2-oxocyclohex-3-ene-1-carboxylate and ammonium acetate in glacial acetic acid. The synthesized compound was characterized by elemental analysis, FT-IR, thermogravimetric analysis (TGA), differential thermal analysis (DTA), UV-Visible, and single-crystal X-ray diffraction. The title compound, ethyl 2-amino-4-(4-fluorophenyl)-6-phenylcyclohexa-1,3-diene-1-carboxylate, C₂₁H₂OFNO₂, crystallizes in the orthorhombic space group Pbca with the following unit-cell parameters: a = 17.417(2), b = 9.7287(9), c = 21.014(2) Å, and Z = 8. The crystal structure was solved by direct methods using single-crystal X-ray diffraction data collected at room temperature and refined by full-matrix least-squares procedures to a final R-value of 0.0644 for 1616 observed reflections. An intramolecular N–H…O hydrogen bond generates an S(6) graph-set motif. In the crystal, molecules are linked by N–H…O hydrogen bonds, forming a two-dimensional network.     

Crystal structure,spectroscopic investigations,and density functional studies of (Z)-2-(1H-imidazol-1-yl)-1-(3-methyl-3-mesitylcyclobutyl)ethanone oxime

The title molecule, (Z)-2-(1H-imidazol-1-yl)-1-(3-methyl-3-mesitylcyclo-butyl)ethanone oxime (C₁₉ H₂₅ N₃ O), was prepared and characterized by¹H-Nuclear magnetic resonance (NMR), ¹³C-NMR, infrared spectroscopic methods, and X-ray single-crystal determination. The compound crystallizes in the orthorhombic space group P c c n with a = 31.4660(17) Å, b = 11.2140(7) Å, and c = 10.0710(8) Å. In addition to molecular geometry from X-ray determination, vibrational frequencies and gauge, including atomic orbital, ¹H- and ¹³C-NMR chemical shift values of the title compound in the ground state, were calculated using the density functional method with the 6-31G(d) basis set. The calculated results show that the optimized geometries can well reproduce the crystal structure. Besides, the theoretical vibrational frequencies and chemical shift values show good agreement with experimental values. The predicted nonlinear optical properties of the title compound are greater than those of urea. Density functional theory calculations of molecular electrostatic potentials, frontier molecular orbitals, and thermodynamic properties of the title compound were carried out at the B3LYP/6-31G(d) level of theory.     

Crystal structure of (Z)-1-(sec-butyl)-3-(4-dimethylaminophenyl)-2-(1H-1,2,4-triazol-1-yl)propen-2-one

The crystal structure of the title compound is determined by X-ray diffraction studies. The structure is solved by the direct method. The experimental data are obtained on a DAR-UMB diffractometer by the θ-θ/2θ scan technique using MoK _α radiation. The crystal is monoclinic, a = 17.913(3) Å, b = 17.239(3) Å, c = 5.501(5) Å, γ = 74.4(3)°, space group P2₁/a, Z = 4 for C₁₇H₂₂N₄O, and ρ_calcd = 1.211 g/cm³. The molecule consists of the phenyl and triazole rings and the dimethylamino, carbonyl, and isopropyl groups attached to the rings. The dihedral angle between the rings is 67.4°. The carbonyl oxygen atom and the triazole ring are in the trans position relative to each other. The N-C-C-O torsion angle is 172.8°. The molecule is in the Z isomeric form.     

Crystal structure and spectroscopic study of 4-(N-acetyl) cysteinyl-6,7-dimethoxy-2,2-dimethyl-3-hydroxybenzo-1H-pyran,a potential metabolite of glutathione conjugation of precocene II 3,4-epoxide

The X-ray crystal structure of the title compound has been determined. The crystals are monoclinic:P2₁/a, a=9.804(7),b=20.544(4),c=13.288(3) Å,=105.94(4)°,V _c=2561.9 ų,Z=4,D _x=1.39Mg m^–3, (MoK)=0.71069 Å. The structure was solved by direct methods and refined with 2147 reflections to a finalR value of 0.072. The 1h-pyran ring departs from ideal symmetry towards a half-chair conformation. Mass, IR, and¹H NMR spectra are also reported.     

X-ray crystallography of methyl (6-amino-5-cyano-2-methyl-4-(2-nitrophenyl)-4<Emphasis Type="Italic">H</Emphasis>-pyran)-3-carboxylate

The organic carbonitrile namely methyl (6-amino-5-cyano-2-methyl-4-(2-nitrophenyl)-4H-pyran)- 3-carboxylate is synthesized via one-pot multi-component reaction at room temperature using commercially available urea as inexpensive and environmentally benign organo-catalyst and its crystal structure is determined by X-ray technique. The crystals are monoclinic, sp. gr. C2/c, a = 12.3069(8) Å, b = 9.7023(7) Å, c = 24.812(2) Å, β = 94.862(6)°, Z = 8. The dihedral angle between pyran and phenyl rings is 87.8(1)°; the pyran ring is almost planar The dihedral angle between the mean planes of phenyl ring and nitro group is 44.4(2)°. The crystal structure is stabilized by N?H···N and N?H···O hydrogen bonds. In addition, C?H···π interactions are also observed in the crystal structure.     

Synthesis and structure of methyl 8-allyl-6-bromo-2-methyl-1,2,3,4-tetrahydroquinoline-4-carboxylate

The compound C₁₅H₁₈NO₂Br was synthesized and characterized by X-ray diffraction. The crystals belong to the monoclinic system, sp. gr. P2₁/n, a = 8.913(2) Å, b = 23.637(6) Å, c = 13.892(3) Å, β = 90.31(2)°, Z = 8, V = 2926.8(12) ų, ρ_calc = 1.472 g/cm³. The bond lengths and bond angles in two molecules are equal within an experimental error and are typical of this class of compounds. The conformational differences of the saturated heterocyclic and methoxycarbonyl fragments of the molecules result in the presence of two crystallographically independent molecules in the crystal structure.     

Crystal structure and spectroscopic study oftrans-diaquabis(2-benzoylpyridine)copper(II) nitrate

trans-Diaquabis(2-benzoylpyridine)copper(II) nitrate has been prepared and characterized by spectroscopic methods and X-ray crystallography. The complex exhibits strong infrared carbonyl absorption at 1655 cm^–1 and a broad d-d band centered about 14,090 cm^–1. The crystals are monoclinic, space groupP2₁/c witha=7.872(1),b=14.573(3),c=11.132(1) Å,=102.79(1)°,Z=2, andR _F =0.049 for 2440 observedMo-K reflections. The crystal structure consists of a packing of centrosymmetric [Cu(2-benzoylpyridine)₂(H₂O)₂]²⁺ cations and nitrate ions, which are interlinked by hydrogen bonds to form thick layers corresponding to the (100) family of planes. The coordination geometry about the copper atom is an elongated octahedron with aqua ligands occupying the axial positions. The measured bond distances are: Cu-O(aqua)=2.256(3), Cu-O(L)=2.068(2), and Cu-N=1.965(2) Å.Mr. Wang is on leave from Central Laboratory, Nankai University, Tianjin, China.     

Synthesis and Crystal Structure of (E)-1-(2,3-Dihydroxybenzlidene)-4,4-Dimethythiosemicarbazide

Abstract  

The Schiff base C₁₀H₁₃N₃O₂S is monoclinic, having unit cell parameters a = 9.788(1) ?, b = 9.615(1) ?, c = 12.605(1) ?, β = 108.41(1)° and V = 1125.56(2) ?³ and belongs to P2_1/n space group. The molecule is almost planar. The two hydroxyl groups present on the phenyl ring are involved in intermolecular H-bonding, which results in the stacking of molecules in the anti-parallel fashion leading an interesting network of channels. Besides this C–H⋯π and π–π (edge to edge) interactions appear to provide stability to the crystal lattice.     

Synthesis, crystal structure, and molecular modeling (AM1) of Methyl 6-chloro-4-(2-chlorophenyl)-5-formyl-2-methyl-1, 4-dihydropyridine-3-carboxylate

The synthesis and structural characterization of Methyl 6-chloro-4-(2-chlorophenyl)-5-formyl-2-methyl-1,4-dihydropyridine-3-carboxylate is described. The structure was refined to R₁ = 0.0470 for 2665 reflections (with I > 2(I)). Crystal data: C₁₅H₁₃C₁₂NO₃, monoclinic,space group P2₁/c, a = 11.163(9), b = 14.484(8), c = 9.422(7) Å, V = 1512.9(19) ų, Z = 4. The results of crystallographic and molecular modeling (AM1) were compared. The Cl atom attached to the phenyl group has two possible orientations, having 75% (sp) and 25% (ap) occupancy, respectively. The molecules in the crystal are held together by means of intermolecular hydrogen bonds of the type N=H...O and by C=H...O interactions.     

Crystal structure and spectroscopic study of 2-[(2,6-dichlorophenyl)amino]phenylacetoxyacetic acid (Aceclofenac)

The crystal structure of the title compound has been determined. The crystals are monoclinic:P2₁ n(NO. 14),a=12.279(7),b=8.223(1),c=15.504(7)Å,=96.16(2)°,V _c =1556(2)ų,Z=4,D _x =1.511 g cm^–3,=(MoK)=0.71069 Å. The structure was solved by direct methods and refined with 1970 reflections to a finalR value of 0.057. Analytical, mass, spectral, and physicochemical data are also reported.     

Crystal structure of 2-{(R)-1-hydroxy-1-[(2S)-1-tritylaziridin-2-yl] methyl}acrylate and spectroscopic properties of the (R,S) and (S,S) stereoisomers

The crystal and molecular structure of 2-{(R)-1-Hydroxy-1-[(2S)-1-tritylaziridin-2-y1] methy1}acrylate is described. Crystal data: C₂₆H₂₅NO₃, orthorhombic, space group P2₁2₁2₁, a = 9.6954(5), b = 13.1458(5), c = 16.7885(7) Å, V = 2139.8(2) ų, Z = 4. The (R,S) diastereomer shows an intramolecular hydrogen bonding N···H—O under formation of a five-membered ring with N···O distance of 2.664 Å. IR, ¹H NMR and ¹³C NMR data are discussed. The ¹H NMR of the (R,S) diastereomer shows a singlet- whereas the (S,S) diastereomer exhibits a doublet-pattern for the hydroxyl proton.     

Crystal structure of 1-(o-tolyl)-naphthalene

1-(o-Tolyl)-naphthalene was obtained in the synthesis of the 1,8-disubstituted analogue. Crystallographic analysis established orthogonal alignment of the ring systems, in agreement with calculations to investigate the existence of rotamers due to restricted rotation.