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.     

(<Emphasis Type="Italic">E</Emphasis>)-2-[(2-Bromophenylimino)methyl]-5-methoxyphenol: X-ray and DFT-calculated structures

The crystal structure of (E)-2-[(2-Bromophenylimino)methyl]-5-methoxyphenol is determined by using X-ray diffraction and then the molecular structure is investigated with density functional theory (DFT). X-Ray study shows that the title compound has a strong intramolecular O-H…N hydrogen bond and three dimensional crystal structure is primarily determined by C-H…π and weak van der Waals interactions. The strong O-H…N bond is an evidence of the preference for the phenol-imine tautomeric form in the solid state. Optimized molecular geometry is calculated with DFT at the B3LYP/6-31G(d,p) level. The IR spectra of compound were recorded experimentally and calculated to compare with each other. The results from both experiment and theoretical calculations are compared in this study.     

Synthesis, Crystal and Molecular Structure of 1-(2-Chlorobenzyl)-2-methylthio-1H-benzimidazole

Abstract  

1-(2-Chlorobenzyl)-2-methylthio-1H-benzimidazole compound has been synthesized and characterized by elemental analysis, IR and ¹H-NMR spectroscopy and single crystal X-ray diffraction. The compound crystallizes in the triclinic space group P-1 with unit cell parameters a = 17.201 ?, b = 5.873 ?, c = 24.791 ?, α = 67.410(10)°, β = 74.083(11)°, γ = 81.858(12)°. In the crystal packing, no classic hydrogen bonds are founded, but C–H···π interactions are being between the molecules. The molecular geometry and vibrational frequencies of (C₁₅H₁₃ClN₂S) in the ground state have been calculated by using Hartree–Fock (HF) and Density Functional Method (DFT/B3LYP) with 6-31G(d) basis set. The optimized geometric bond lengths and bond angles obtained by using HF and DFT (B3LYP) show the best agreement with the experimental data.     

Hexakis(4-phormylphenoxy)cyclotriphosphazene: X-ray and DFT-calculated structures

The crystal structure of hexakis(4-phormylphenoxy)cyclotriphosphazene is determined by using X-ray diffraction and then the molecular structure is investigated with density functional theory (DFT). X-Ray study shows that the title compound has C-H…π interaction with phosphazene ring. The molecules in the unit cell are packed with Van der Waals and dipole-dipole interactions and the molecules are packed in zigzag shaped. Optimized molecular geometry is calculated with DFT at B3LYP/6-311G(d,p) level. The results from both experimental and theoretical calculations are compared in this study.     

1-[2-(p-Tolyl)-1-diazenyl]-3-({3-[2-(p-tolyl)-1-diazenyl] perhydrobenzo[d]imidazol-1-yl}methyl)perhydrobenzo[d]imidazole: synthesis,characterization and X-ray crystal structure

1-[2-(p-Tolyl)-1-diazenyl]-3-({3-[2-(p-tolyl)-1-diazenyl]perhydrobenzo[d]imidazol-1-yl}methyl)perhydrobenzo[d]imidazole(1) has been synthesized by reactionof a mixture of 1,2-diaminocyclohexane and formaldehyde withp-toluene diazonium chloride inaqueous solution. The product has been characterized by IR and NMRspectroscopy and elemental analysis. A crystal grown from solution ina mixed solvent system of ethyl acetate and hexanes was analyzed byX-ray crystallography. The solution of the crystal structure of(1) is important in establishing theconnectivity of this molecule and other compounds of similarstructure. The crystal structure of (1) is compared with the previously reportedstructure of the p-cyano analogue(2). Compounds (1) and (2)differ principally in the relative orientation of the heterocyclicrings; in (1), the molecule has adistinct V-shape, whereas compound (2) adopts a more extended conformation.Significant conjugation within the triazene moieties is evident inboth (1) and (2), as manifested in the N465=N andN–N bond lengths. The conjugation is greater in (2) due to the extended conjugation through tothe nitrile group. The title compound (1){C₂₉H₄₀N₈}crystallizes in the monoclinic, space group C2/c, with lattice constants: a = 30.532(6) ?,b =5.9050(12) ?, c= 15.463(3) ?, α = 90°,β = 99.94(3)°, γ = 90°,V =2746.0(10) ?³, Z = 4, D _c =1.209 mg m⁻³,F(000) = 1076, R ₁ = 0.0785,wR ₂= 0.1877.     

Synthesis and Crystal Structure of Compound 1-Phenyl-2-(1H-1,2,4-triazolo-yl)-3-phenyl-propen-1-one and 1-Diphenyl-3-(1,2,4-triazolo-yl)-1H,4H-1,5-benzothiazepine

Abstract  

The crystal structures of the compounds 1-phenyl-2-(1H-1,2,4-triazolo-yl)-3-phenyl-propen-1-one (2), and 2,4-diphenyl-3-(1,2,4-triazolo-yl)-1H,4H-1,5-benzothiazepine (3) were obtained by single crystal X-ray diffraction. Compound 2 crystallizes in the triclinic system with space group P − 1, a = 8.5553(17) ?, b = 9.6229(19) ?, c = 9.924(2) ?, α = 106.16(3)°, β = 108.03(3)°, γ = 105.14(3)°, V = 690.1(2) ?³, Z = 2. The compound 3 crystallizes in the orthorhombic system with space group Pbca, a = 12.904(3) ?, b = 15.864(3) ?, c = 19.140(4) ?, α = 90°, β = 90°, γ = 90°, V = 3918.3(14) ?³, Z = 8. H-bonds and π–π stacking are the main non-bonding interactions in the molecular structure. Details of the synthesis, structures, and spectroscopic properties of the two compounds are discussed.     

Synthesis, Molecular Structure and Antioxidant Activity of (E)-4-[Benzylideneamino]-1,5-dimethyl-2-phenyl-1H-pyrazol-3(2H)-one, a Schiff Base Ligand of 4-Aminoantipyrine

Abstract  

In this study, the title compound, C₁₈H₁₇N₃O (M _r = 291.35), was synthesized by the condensation reaction of 4-amino-1,5-dimethyl-2-phenylpyrazole-3-one and benzaldehyde. Single-crystal X-ray diffraction data revealed that this compound adopts a trans configuration around the central C=N double bond. It crystallizes in the monoclinic, space group P2₁/c with a = 12.9236(17) ?, b = 6.8349(9) ?, c = 17.072(2) ?, β = 90.316(3)°, V = 1508.0(3) ?³, Z = 4, D _c = 1.283 Mg/m³, F(000) = 616, μ = 0.082 mm⁻¹, R = 0.0442, and wR = 0.0936. Two different planes exist within the molecule; e.g. the pyrazolone and benzylidene groups attached to C9 of the pyrazolone ring are almost coplanar, whereas the phenyl group attached to the N1 of the pyrazolone ring is in another plane. Density functional theory (DFT) and time-dependent DFT calculations were performed to predict the electronic structure and absorption spectra of (E)-4-[benzylideneamino]-1,5-dimethyl-2-phenyl-1H-pyrazol-3(2H)-one, a schiff base ligand of 4-aminoantipyrine using B3LYP/6-311G basis set on the AM1 optimized geometry. The predicted vibrational frequencies using the B3LYP/6-311G method were in strong agreement with the experimental IR spectra. The time dependent DFT calculations were used to evaluate the electronic absorption spectrum and three electron transition bands, which were mainly derived from the contribution of n → π* and π → π* transitions, were observed in both the experimental and predicted UV–Vis spectra. A maximum emission band at 370 nm was observed in the fluorescence spectra of the title compound. In addition, the title compound showed good DPPH antioxidant activity.     

Synthesis,crystal structure,and spectral studies of 10-(2-Benzothiazolylazo)-9-phenanthrol

10-(2-Benzothiazolylazo)-9-phenanthrol (L) is prepared by a reaction of 2-hydrazinobenzothiazol with 9,10-phenanthrenequinone. The crystal and molecular structure of the L·CHCl₃ solvate is determined by X-ray diffraction. The data of the X-ray diffraction study, as well as IR, ¹H NMR, and electronic absorption spectra, indicate that in the crystal state and solutions the L molecule exists in the form of a quinohydrazone tautomer (b) (s-trans, cis) stabilized by the intramolecular N₂-HN₂…O1 hydrogen bond. The “mobile” H atom is located at the N2 atom of the azo group. The benzothiazolyl and phenanthrenequinone fragments are nearly coplanar. Spectroscopic criteria for the state of L in various media are determined based on the data of IR, ¹H NMR, and electronic absorption spectroscopy and the results of the Pariser-Parr-Pople quantum-chemical calculations.     

One Dimensional Hydrogen Bonded Arrangement in New Schiff-Base Compound (<Emphasis Type="Italic">E</Emphasis>)-2-(2,5-dimethoxybenzylideneamino)phenol (1): Synthesis,Characterization, Crystal Structure and Conformational Studies

Abstract  

New Schiff-base compound (E)-2-(2,5-dimethoxybenzylideneamino)phenol (1) was synthesized and characterized by elemental analyses, FT-IR and ¹H-NMR spectroscopy and single crystal X-ray diffraction. Molecular orbital calculation has been carried out for 1 by using HF method at 6-31G basis set. The title compound 1 crystallizes in monoclinic system, space group C2/c, with a = 19.4581(13) ?, b = 9.5805(5) Ǻ, c = 13.8431(7) Ǻ, β = 93.471(2)°, V = 2575.9(3) Ǻ³ and Z = 8. In the crystal structure two molecules are stabilized by a pair of intermolecular O1–H1···N1ⁱ hydrogen bonds. The dimeric units are further linked via C6–H6···O3ⁱⁱ hydrogen bond.     

The isomorphous substitution of 2H+ for the Cu2+ cation in the complex of bis(aminoguanidine)copper(II): Crystal structures of (Cu0.61H0.78Agu2)B12H12 and (HAgu)2B12H12

An X-ray diffraction study of the (Cu_0.61H_0.78 Agu ₂)B₁₂H₁₂ (I) mixed crystal and one of its components (HAgu)₂B₁₂H₁₂ (II) is performed at 160 K (R = 0.0312 and 0.0345, respectively). Crystals I and II are isostructural. In I, two H⁺ ions partially substitute the Cu²⁺ cation, resulting in a combination of [CuAgu ₂]²⁺ and (HAgu ₂)₂₊ cations in the structure. The cations and polyhedral B₁₂H₁₂²⁻ anions have centrosymmetric structures. A square planar environment for the Cu atom is formed by four N atoms of two Agu molecules, which close five-membered chelate cycles [Cu-N, 1.9702(13) and 2.0261(10) ?]. The distant apical vertices are occupied by H atoms of the B₁₂H₁₂²⁻ anions [Cu…H, 2.805(14) ?]. In the dimeric (HAgu ₂)²⁺ cations, the proton that substitutes for the Cu²⁺ cation forms a three-center N(1)-H…N(4),N(4)′ hydrogen bond which consists of intramolecular and an intermolecular components. In crystal II, the N(1)…N(4) and N(1)…N(4)′ distances [2.685(1) and 3.111(1) ?] are longer than in I [2.610(2) and 3.027(2) ?]. In I, the Cu…H interactions connect [CuAgu ₂]²⁺ cations and B₁₂H₁₂²⁻ anions into chains. In the cells that contain the (HAgu ₂)²⁺ dimeric cation, the chains are retained due to the secondary N-H…(B-H) interactions. Numerous weak secondary interactions between the cations and anions form three-dimensional frameworks in structures I and II.     

X-ray structure analysis of 1-(4-bromophenyl)-3-(4-chlorophenyl)-prop-2-en-1-one

The title compound crystallizes in the monoclinic space group P2₁/c with unit cell parameters a = 15.6239(15) ?, b = 14.0537(14) ?, c = 5.8396(5) ?, β = 92.666(3)°, V = 1280.8 (2) ?³, and Z = 4. The final reliability index is 0.0538 for 2921 observed reflections. Two phenyl rings of the title molecule are not coplanar, with a dihedral angle of 46.3(0)°. The molecular planarity of this substituted chalcone is strongly affected by the 4′-bromo group. The crystal cohesion is accentuated by π···π, C–H···Br interactions and R₃ ¹ (11) hydrogen bond.     

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.     

Synthesis,Characterization and Antibacterial Activity of <Emphasis Type="Italic">N</Emphasis>-(2,3,4-Trimethoxy-6-methylbenzylidene)-2-methyl-benzenamine

Abstract  The title compound N-(2,3,4-trimethoxy-6-methylbenzylidene)-2-methyl-benzenamine (C₁₈H₂₁NO₃, M _r = 299.36) was synthesized and characterized by elemental analysis, IR spectra and single crystal X-ray diffraction. The crystal belongs to monoclinic, space group P2₁/n, with a = 7.2804(5), b = 8.5909(9), c = 26.117(3) ?, β = 92.056(2)°, V = 1,632.4(3) ?³, Z = 4, D _c = 1.218 g cm⁻³, λ = 0.71073 ?, μ(Mo Kα) = 0.083 mm⁻¹, F(000) = 640. The final refinement gave R = 0.0497, wR(F ²) = 0.1157 for 2,879 observed reflections with I > 2σ(I). X-ray diffraction analysis reveals that the dihedral angle between the two phenyl rings is 25.9 (2)°. The molecule adopts a trans configuration about the central C=N functional bond. The crystal structure is stabilized by C–H…O hydrogen bonds and π–π stacking interactions. The title compound possesses moderate antibacterial activity. Graphical Abstract  The title compound N-(2,3,4-trimethoxy-6-methylbenzylidene)-2-methyl-benzenamine (C₁₈H₂₁NO₃, M _r = 299.36) was synthesized and characterized by elemental analysis, IR spectra and single crystal X-ray diffraction. The crystal belongs to monoclinic, space group P2₁/n, with a = 7.2804(5), b = 8.5909(9), c = 26.117(3) ?, β = 92.056(2)°, V = 1,632.4(3) ?³, Z = 4, D _c = 1.218 g cm⁻³, λ = 0.71073 ?, μ(Mo Kα) = 0.083 mm⁻¹, F(000) = 640. The final refinement gave R = 0.0497, wR(F ²) = 0.1157 for 2,879 observed reflections with I > 2σ(I). X-ray diffraction analysis reveals that the dihedral angle between the two phenyl rings is 25.9 (2)°. The molecule adopts a trans configuration about the central C=N functional bond. The crystal structure is stabilized by C–H…O hydrogen bonds and π–π stacking interactions. The title compound possesses moderate antibacterial activity.      

Structural Characterization of New Compound from the Ring-Opening Reaction of 3-(1H-1,2,4-triazol-1-yl)-1,5-Benzothiazepine with Phenylonitrile Oxide

Abstract  

The crystal structure of the product (Z)-2-((Z)-((Z)-1,3-diphenyl-2-(1H-1,2,4-triazol-1-yl)allylidene)amino)phenyl N-hydroxybenzimidothioate (4) was obtained by single crystal X-ray diffraction. The title compound, C₃₀H₂₃N₅OS (4), crystallizes in the triclinic space group, P-1, with unit cell parameters a = 8.3306(17) ?, b = 11.394(2) ?, c = 14.560(3) ?, α = 78.75(3)o, β = 89.96(3)o, γ = 70.56(3)o, Z = 2. In the crystal structure, adjacent molecules are linked by O–H···N hydrogen bonds. H-bonds and π–π stacking are the main non-bonding interactions in the molecular structure and give support to molecular packing stability. In addition, the structure is supported by a weak intermolecular C–H···Cg π-ring interaction. Detail of the synthesis, structures, and spectroscopic properties of the title compound is discussed.     

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.     

Crystallographic and Computational Analysis of the Supramolecular Structure of 2,5-Dimethylpyrazolo[1,5-a]pyrimidin-7(4H)-one

Abstract  

The structure of 5-dimethylpyrazolo[1,5-a]pyrimidin-7(4H)-one 1 has been determined by X-ray crystallography. The compound 1 crystallizes in the space group P−1 with two molecules in the asymmetric unit solvated with one molecule of the acetic acid The unit cell parameters are a = 8.796(1) ?, b = 10.531(1) ?, c = 10.680(1) ?, α = 96.901(2)o, β = 98.135(2)o, γ = 107.248(2)o. In the crystal molecules A and B are linked into R ₂²(9) hydrogen bonded rings and these rings form chains parallel to [101] Overall, the supramolecular structure 1 consists of two hydrogen bonded and two π–π stacking dimers. An energetic interplay between these dimers has been studied using B3LYP DFT calculations. In addition π–π interactions are analyzed using the Bader’s atoms in molecules’ (AIM) theory.     

Structure of a New Bioactive Agent Containing Combined Antibacterial and Antifungal Pharmacophore Sites: 4-{[(<Emphasis Type="Italic">E</Emphasis>)-(5-Bromo-2-hydroxyphenyl)methylidene]amino}-<Emphasis Type="Italic">N</Emphasis>-(5-methyl-1,2-oxazol-3-yl)benzenesulfonamide

Abstract  

The title compound (3), C₁₇H₁₄BrN₃O₄S, is a Schiff base compound of 5-bromosalicylaldehyde (1) and sulfamethoxazole (2). The structure of (3) was determined by spectral (IR, ¹H and ¹³C NMR), elemental analyses and X-ray diffraction data. Compound (3) crystallizes in the monoclinic space group C2/c, with a = 31.936(3), b = 6.2571(5), c = 16.903(1) ?, β = 94.867(8), V = 3365.5(5) ?³, Z = 8. In the molecule of compound (3), the molecule is bent at the S atom with a C–SO₂–NH–C torsion angle of −86.3(3)°. Pairs of molecules, related by inversion centres, form intermolecular N–H···N hydrogen bonds to produce a dimer. An intramolecular phenolic O–H···N hydrogen bond is also formed. Intermolecular hydrogen bonding and π–π stacking hold the molecules together. The average distance between stacked benzene ring planes is 3.625(2) ?.     

A Crystallographic Study of a Highly Substituted Imidazolinone, (3S,4S,5R)-3-(((S)-4-((1H-Indol-3-yl)Methyl)-5-Oxo-4,5-Dihydro-1H-Imidazol-2-yl)Amino)-4-((Tert-Butyldimethylsilyl)Oxy)-5-Hydroxypiperidin-2-One

Abstract  

The title compound 1 has been prepared from the condensation product of a silyl protected amino-oxazoline lactam (3) and Cbz-protected l-tryptophan (4) after hydrogenolysis of the carboxybenzyl protection group. The synthesis and crystal structure of 1 is described. The compound crystallized from DMSO in the monoclinic system, P2₁ space group with unit cell parameters a = 9.4029(25), b = 6.2828(12), c = 20.681(45), and β = 96.505(16), Z = 2 and a cell volume of V = 1213.9(2) ?³. In the crystal lattice, 1 forms an extensive hydrogen bonded framework consisting of interconnected dimeric chains.     

Crystallographic and conformational analysis of 1,3-bis(2,4-dimethoxyphenyl)imidazolidine-2-thione

The molecular and crystal structures of the title compound, C₁₉H₂₂N₂O₄S, were determined by single crystal X-ray diffraction technique. The title compound crystallizes in space group F d d 2, with a = 30.785(3) ?, b = 10.6455(9) ?, c = 11.0036(8) ?, Z = 8, D _calc = 1.379(2) g cm⁻³, μ(Mo-K_α) = 0.207 mm⁻¹, and its crystal system is orthorhombic. The structure was solved by direct methods and refined to a final R = 0.042 for 1530 reflections with I > 2σ (I). There is a half-independent molecule in the asymmetric unit. The title molecule has twofold rotational symmetry along with the C–S bond. Classically no hydrogen bond is found in the crystal structure. The crystal structure is stabilized by π–π stacking and edge to face (C–H…π-ring) interactions. To elucidate conformational features and steric hindrances of the title molecule, selected torsion angle is varied from −180° to +180° in every 10° and thus molecular energy profile is calculated by PM3 semi-empirical method.Supplementary materials CCDC 261789 contains the supplementary crystallographic data for this paper. These data can be obtained free of charge via www.ccdc.cam.ac.uk/data_request/cif, by emailing data_request@ccdc.cam.ac.uk, or by contacting The Cambridge Crystallographic Data Centre, 12, Union Road, Cambridge CB2 1EZ, UK; fax: $+$44 1223 336033.     

Synthesis, Structural Characterization and Spectroscopic Properties of 1,2-Bis[4-(3,5-dimethyl-1H-pyrazol-1-yl)-2-oxobutyl]benzene

Abstract  

The crystal structure of the title compound C₂₂H₃₀N₄O₂·H₂O (L), has been determined using X-ray diffraction at 293 K. The crystal of 1,2-bis[4-(3,5-dimethyl-1H-pyrazol-1-yl)-2-oxobutyl]benzene is in triclinic crystal system with space group P(−1) (Z = 2), lattice parameters a = 8.225(6) ?, b = 10.967(6) ?, c = 12.903(6) ?, V = 1119.1(11) ?³. Analyses of single crystals of L, crystallized from dichloromethane/diethyl ether (1:1), revealed that the molecules are arranged in couples, which adopt a pseudo chair conformation, by means of intermolecular O–H···N hydrogen bonding interactions. Moreover, the extended structure revealed a 1D chain caused by several C–H···N intermolecular interactions.