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.     

Molecular and Crystal Structure of 2-{(<Emphasis Type="Italic">E</Emphasis>)-[(5-Chloro-2-methoxyphenyl)imino]methyl}-4-nitrophenol

The molecular structure of the title compound, C₁₄H₁₁ClN₂O₄, was determined by single crystal X-ray diffraction. The compound crystallizes in the monoclinic sp. gr. P2₁/c with Z = 4. The title compound, C₁₄H₁₁ClN₂O₄, is a Schiff base which adopts the phenol-imine tautomeric form in the solid state.The molecule is almost planar and the dihedral angle between the planes of two aromatic ring is 2.2(1)°. The molecular structure is stabilized by intramolecular O–H···N hydrogen bond which generates a six-membered ring. In the crystal structure, the molecules are linked together by intermolecular C–H···O interactions.     

Synthesis,Crystal Structure,Spectroscopic and Electronic Properties of (E)-Trans-2-(2-(Biphenyl-4-ylmethylene)Hydrazinyl)-4-(3-Methyl-3-Phenylcyclobutyl)Thiazole

Abstract  

A new compound of (C₂₇H₂₅N₃S) has been synthesized and characterized by ¹H NMR, ¹³C NMR, IR, UV-Visible spectroscopy, and single crystal X-ray diffraction. The compound crystallizes in the monoclinic space group P2₁/c and crystals of (I) were found approximately 0.5:0.5 ratio to be twinned. The crystal structure is stabilized by N–H···N inter molecular hydrogen bonding. In addition to the molecular geometry and dimeric structure from X-ray experiment, the optimized molecular geometry for monomer and dimer, vibrational frequencies, atomic charges distribution, and total energies of the title compound in the ground state have been calculated using ab initio method. Density Functional Theory (B3LYP) and Hartree-Fock (HF) methods with basis sets 6-31G(d, p) and 3-21G were used in the calculations. Calculated frequencies are in good agreement with the corresponding experimental data. UV-Vis absorption spectra of the compound have been ascribed to their corresponding molecular structure and electrons orbital transitions.     

Crystal and molecular structure of 2-(1,3-benzothiazol-2-yl)-2-(4-tert-butylcyclohexylidene)ethanonitrile

The crystal and molecular structure of the title compound (C₁₉H₂₂N₂S) has been investigated by single crystal X-ray methods. The crystals are orthorhombic, space groupPbca, with cell dimensions:a=12.082(2)Å,b=11.460(2)Å,c=25.128(4)Å. The structure was solved by direct methods, and refined with 1225 independent reflections by a full-matrix, least-squares procedure, which converged toR=0.042. The benzene and thiazole planes are coplanar and the cyclohexane ring adopts a chair conformation.     

Crystal and Molecular Structure of <Emphasis Type="Italic">N</Emphasis>-(Phenylthio)phthalimide

The title compound N-(Phenylthio)phthalimide has been synthesized and characterized by FT-IR, NMR, and X-ray single-crystal determination. The compound crystallizes in the triclinic sp. gr. \(P\bar 1\) with Z = 2. The title compound is not planar. The dihedral angle between the phthalimide and phenyl ring systems is 77.41(8)°. The crystal structure is stabilized by intermolecular π...π and C–H...π interactions.     

Synthesis and crystal structure of 1-(4-bromobenzyl)-4-methyl-2,6,7-trioxabicyclo[2.2.2]octane

1-(4-Bromobenzyl)-4-methyl-2,6,7-trioxabicyclo[2.2.2]octane, C₁₃H₁₅BrO₃, has been synthesized from 4-bromophenylacetic acid chloride via the oxetan ester (3-methyl-3-oxetanyl)methyl-2-(4-bromophenyl)acetate. The crystal structure of the title compound has been determined at low temperature (120 K), by X-ray diffraction methods. This compound crystallizes in the monoclinic space group P2₁/n (No. 14), Z = 4, with lattice parametersa = 6.019(5), b = 20.990(5), c = 9.915(2) Å, and = 101.29(1)°.     

Synthesis,Crystal Structure,Spectral and Thermal Studies of (<Emphasis Type="Italic">E</Emphasis>)-4-Dimethamino[(1-phenylethyl)iminomethyl]benzyne

Abstract  

Schiff-base compound (E)-4-dimethamino[(1-phenylethyl)iminomethyl]benzyne was synthesized and characterized by elemental analyses (CHN), FT-IR and ¹H-NMR spectroscopic techniques and thermogravimetric analyses (TG). Crystal structure of the title compound was obtained by single crystal X-ray diffraction. The title compound crystallizes in the monoclinic space group P2₁ with unit cell parameters: a = 8.5283(2), b = 6.0699(2), c = 13.6997(4) Ǻ, β = 91.471(2)°, V = 708.94(4) Ǻ³ and Z = 2.     

Studies on a new Rb3H9(PO4)4 crystal

A new type of trirubidium nonahydrogen tetraphosphate, Rb₃H₉(PO₄)₄, crystal has been crystallized. Differential scanning calorimetry (DSC) and X‐ray diffraction measurements have been performed on the title compound. The crystal does not undergo any structural phase transition in the temperature range from 120 to 440 K except a melting transition at 399 K. The compound belongs to a monoclinic system with space group C2/c at room temperature. The structure is built on a framework of PO₄ tetrahedra linked by five types of OH‐O hydrogen bonds in the length range from 2.472(4) to 2.679(4) Å. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)     

Synthesis Characterization and Crystal Structure of 2-(3,4,5-trimethoxyphenyl)-1-(4-fluorophenyl)-4,5-diphenyl-1H-imidazole

The title compound, C₃₀H₂₅FN₂O₃, was prepared from the four-component one-pot condensation reaction and the product crystallized using dimethylformamide. The structure of the compound was established by elemental analysis, Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), UV-Visible, and single-crystal X-ray diffraction. The compound crystallizes in the triclinic crystal system with the space group Pī, with unit cell parameters a = 10.286(2) Å, b = 11.795(2) Å, c = 21.331(4) Å, α = 100.270(3)°, β = 90.093(3)°, γ = 90.062(3)°, and Z = 4. The crystal and molecular structure of the title molecule is stabilized by intra-molecular interactions of types C–H···N and C–H···O.     

Spectroscopic Studies and Structure of 4-(3-Benzoylthioureido)benzoic Acid

Abstract  

4-(3-Benzoylthioureido)benzoic acid has been synthesized from the reaction of 4-aminobenzoic acid with benzoyl isothiocyanate. The title compound has been characterized by elemental analysis, MS, FT-IR, ¹H-NMR, ¹³C-NMR and UV–Visible techniques. The structure of the compound has also been examined crystallographically. The title compound crystallizes in the triclinic space group P-1 with a = 3.969(1), b = 13.039(1), c = 13.504(1) ?, α = 96.50(1)°, β = 92.25(1)°, γ = 94.94(1), V = 691.0(1) ?³ and D _x  = 1.444 g cm⁻³, respectively. The crystal structure has been solved by direct methods and refined by full-matrix least squares and found R ₁ = 0.031 and wR ₂ = 0.081 for 2909 observed reflections [I > 2σ(I)].     

Synthesis,Crystal Structure and Spectroscopic Characterization of {6-[2-(2-chlorophenyl)-1,3-thiazol-4-yl]-2-oxo-1,3-benzothiazol-3(2<Emphasis Type="Italic">H</Emphasis>)-yl}acetic acid

Abstract  

The title compound {6-[2-(2-chlorophenyl)-1,3-thiazol-4-yl]-2-oxo-1,3-benzothiazol-3(2H)-yl}acetic acid was prepared and characterized by elemental analyses, FT-IR, ¹H NMR spectroscopy, X-ray diffraction. A quantum-chemical calculation was performed using the CNDO method. In the title compound, C₁₈H₁₁ClN₂O₃S₂, the crystal structure is stabilized by intermolecular hydrogen bonds (C–H···O=C) to form centrosymmetric R₂² R_{2}^{2} (16) dimers and the C–H···O, O–H···N, and C–H···N interactions generating the graph set motifs R₂² R_{2}^{2} (9) and R₂² R_{2}^{2} (22).     

X-Ray diffraction and vibrational spectroscopic study of 2-chloro-N-{4-[3-(2,5-dimethylphenyl)-3-methylcyclobutyl]-thiazol-2-yl}-acetamide

The title compound C₁₈H₂₁ClN₂SO crystallizes with Z = 4 in space group P2₁/c. The structure of the title compound was characterized by ¹H-NMR, ¹³C-NMR, IR and single crystal diffraction. There are an intermolecular N-H…O hydrogen bond and a C-H…π interactions in crystal packing. In addition to the molecular geometry and packing obtained from X-ray experiment, the molecular geometry and vibrational frequencies of the title compound in ground state have been calculated using density functional theory method DFT (B3LYP) with 6-31G (d, p) basis set. Calculated frequencies, bond lengths, angles and dihedral angles are in good agreement with the corresponding experimental data.     

Synthesis and crystal structure of (1R,2R)-N,N′-bis(4-toluenesulfonyl)-1, 2-di(4-methoxylphenyl)ethylenediamine

The reaction of (1R,2R)-1,2-di(4-methoxylphenyl)ethylenediamine with p-toluene sulfonyl chloride affords the title compound C₃₀H₃₂N₂O₆S₂, the structure of which is ascertained by X-ray diffraction. The title compound contains two chiral centre with each C atom in R configuration. Two adjacent molecules are linked by intermolecular hydrogen bonds through sulfonamide nitrogen and sulfonyl oxygen to form a one-dimensional chain alone a axis.     

Synthesis,Crystal Structure and Characterization of (Z)-2-N′-hydroxyisonicotinamidine

The compound (Z)-2-N′-hydroxyisonicotinamidine, (2) was synthesized and characterized by ¹H NMR, FT-IR, FAB-Mass, UV-Visible Spectra, and elemental Analysis. Its molecular structure was solved by single crystal X-ray diffraction method. The title molecule, C₆H₇N₃O is crystallized in the orthorhombic crystal system with the space group Pna2₁ and with unit cell parameters a = 12.5664(8) Å, b = 8.8622(6) Å, c = 5.7953(4) Å, α = 90°, β = 90°, γ = 90°, and Z = 4. The molecular and crystal structure of the title molecule is stabilized by an intramolecular interaction of the type N—H···O, and the intermolecular interactions of types N—H···N and O—H···N.     

Unexpected crystallization and X-ray crystal structure of racemic 1-phenyl-2-(4-pyridyl)ethanol intermediate

We have isolated, by crystallization, the intermediate, 1-phenyl-2-(4-pyridyl)ethanol, from the condensation reaction of 4-methylpyridine with benzaldehyde in which the aim was to obtain the model compound 4-styrylpyridine in absence of a condensing agent. Single crystal X-ray analysis shows the formation of an intermolecular hydrogen bond O–H···N between the nitrogen atom of a pyridine group and the oxygen atom of the OH of the neighboring molecule, which helps to stabilize the crystal structure. Crystal structure determination clearly revealed that the solid is chiral and racemic, as expected. The title compound crystallizes in an orthorhombic system with a space group Pna2₁ with two pairs of R and S enantiomers in each crystal cell (a = 15.591(1) Å, b = 12.691(1) Å, and c = 5.589(1) Å). Spectroscopic NMR data gave evidence that the isolated compound is actually the alcohol just before the dehydration process that yields the double bond of the 4-styrylpyridine.     

Synthesis,Crystallographic and Spectral Studies of 3-(4-(Phenylamino) Phenylamino)Cyclohex-2-Enone

Abstract  

The title compound, 3-(4-(phenylamino)phenylamino)cyclohex-2-enone, β-enaminone of 1,3-cyclohexanedione and p-amino diphenylamine (C₁₈H₁₈N₂O) was prepared and characterized by ¹H-NMR, ¹³C-NMR, Elemental analysis and IR spectroscopy as well as single crystal X-ray diffraction. These results indicate the predominance of the keto-enol tautomerism. Molecular conformation around the central disubstituted benzene ring is affected by the tautomerism and two steric effects between side molecular groups and mono substituted benzene ring. Electron delocalizations due to these effects have been observed in the molecular structure, the structure being stabilized by some intermolecular hydrogen bonds.     

Crystal structure of 3‐(3‐nitrophenylhydrazonocarbonyl)‐(1H)‐1,2,4‐triazole

The title compound, C₁₀H₈N₆O₃, was synthesized by the reaction of 3‐(1H)‐1,2,4‐triazole hydrazine with 3‐nitrobenzaldehyde in ethanol. The single crystal structure has been determined by X‐ray analysis. The crystal belongs to monoclinic system, space group p2₁/c with cell constant, a = 8.0214(17) Å, b = 17.334(4) Å, c = 8.9070(18) Å, V= 1179.4(4) ų. An intramolecular N—H...O and N—H…N hydrogen bond are observed between the ‐NH group with O atom of the carbonyl group and the ‐NH group with N atom. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)     

Crystal and Molecular Structure of 4-methoxy-carbonyl methyl-2,9-bis(phenylsulfonyl)-1,2,3,4-tetrahydro β-carboline : benzene solvate

The crystal structure of the title compound has been determined from X-ray diffraction data. The compound crystallizes from benzene in the monoclinic system, space group P2₁/a, with unit cell parameters: a = 12.676(2), b = 20.333(3), c = 12.947(2) Å, β = 113.12(1)°, Z = 4, V = 3069.0(8) ų. The trial structure was determined by direct methods and refined to a final R-index of 0.044. The six-membered heterocyclic ring adopts half-chair conformation. Of the two phenylsulfonyl groups, the one substituted at the indole nitrogen (N1) is equatorial, while the other (at N2) is axial. The methyl acetate group is approximately perpendicular to the β-carboline moiety.     

Crystallographic and Conformational Analysis of [(Z)-2-ethoxy-6-[(2-hydroxyphenylamino)methylene]cyclohexa-2,4-dienone]

Abstract  The single crystal X-ray diffraction analysis of the title compound, C₁₅H₁₅NO₃, shows that the structure is adopted to its NH tautomeric form and crystallizes in the orthorhombic space group P bcn with a = 21.2424(15) ?, b = 12.7696(9) ?, c = 9.3605(10) ?, Z = 8, V = 2539.1(4) ?³, D _c  = 1.346 g/cm³. The molecular conformation in the crystal is stabilized by an intramolecular H-bond and the crystal structure is stabilized by the bifurcated O–H···O type intermolecular H-bonds. In order to understand the effects on conformational flexibility of the title molecule, molecular energy profile was calculated as a function of the selected torsion angle by means of AM1 semi-empirical method. Index Abstract  Molecular and crystal structure of [(Z)-2-ethoxy-6-[(2-hydroxyphenylamino)methylene]cyclohexa-2,4-dienone], C₁₅H₁₅NO₃, have been determined by single crystal X-ray diffraction study, and conformational analysis of the title molecule with respect to the selected torsion angle has been achieved by AM1 semi-empirical calculations.      

Experimental and Semi-Empirical and DFT Calculational Studies on (<Emphasis Type="Italic">E</Emphasis>)-2-[(2,4-Dichlorophenylimino) methyl]-<Emphasis Type="Italic">p</Emphasis>-cresol

Abstract  

The molecular and crystal structure of the title compound, C₁₄H₁₁Cl₂NO, has been determined by X-ray single crystal diffraction technique. The compound crystallizes in the orthorhombic, space group Pbca with unit cell dimensions a = 7.5537(10) ?, b = 11.5518(13) ?, c = 29.760(4) ?, M _r  = 280.14, V = 2596.8(6) ?³, Z = 8, R ₁ = 0.065 and wR ₂ = 0.191. The title compound exists in the enol–imine tautomeric form with a strong intramolecular O–H···N hydrogen bond. The dihedral angle between the two benzene rings is 37.66(15)°. The asymmetric unit in the crystal structure contains only one neutral molecule. Calculational studies were performed by using AM1, PM3, PM6 semi-empirical and DFT methods. Geometry optimizations of compound have been carried out by using three semi-empirical methods and DFT method and bond lengths, bond and torsion angles of title compound have been determined. Dipole moments (Debye) and the energy parameters of compound (kcal/mol) were calculated by using above mentioned calculation methods. Atomic charge distribution has been obtained from AM1, PM3, PM6 and DFT. In order to determine conformational flexibility on the molecule, molecular energy profile of the title compound was obtained with respect to the selected torsion angle T(N1–C7–C1–C2), which is varied from −180° to +180° in every 10 via PM3 semi-empirical method.