Crystal Structure of 1,7-Bis(4-chlorophenyl)-4-(1,3-dithiolan-2-ylidene)-1,6-heptadiene-3,5-dione

Abstract  The synthesis and crystal structure of 1,7-bis(4-chlorophenyl)-4-(1,3-dithiolan-2-ylidene)-1,6-heptadiene-3,5-dione is described. This compound is a curcuminoid analogue, configurationally symmetric about the C4–C5 atoms and also retains the two fold axis in the crystal phase. This compound crystallizes in the space group C2/c with unit cell parameters a = 19.203(1) ?, b = 13.147(1) ?, c = 8.801(1) ?, β = 112.99(1)°, with half a molecule in the asymmetric unit. The ketenedithioacetal functionality present between the carbonyl groups prevents the possibility of keto-enol tautomerization in this compound. The push-pull nature of the ketenedithioacetal functionality organizes the cinnamoyl groups parallel to each other. Index Abstract  The details regarding synthesis and crystal structure of the title compound which is a curcuminoid analogue is reported in this paper.      

Crystal Structures of 1,7-Bis(furyl)-4-(1,3-dithiolan-2-ylidene)-1,6-heptadiene-3,5-dione and 1,7-bis(thienyl)-4-(1,3-dithiolan-2-ylidene)-1,6-heptadiene-3,5-dione

Abstract  

The title compounds (bis(alkenoyl) ketene dithioacetals) were prepared starting from the cyclic acyl ketene dithioacetal and aromatic aldehydes. These compounds were characterized by IR, ¹H NMR, mass spectral studies and X-ray crystal structure analysis. The bis(furyl) ketene dithioacetal crystallized in the space group P[`\text1] P{\bar{\text{1}}} with unit cell dimensions a = 7.7626(12) ?, b = 9.0217(13) ?, c = 26.827(5) ?, α = 86.271(14)°, β = 87.643(14)°, γ = 66.286(11)° and the structure was refined to an R-factor of 0.0528 while bis(thienyl) ketene dithioacetal crystallized in the space group P2₁/c with unit cell dimensions a = 10.2433(9) ?, b = 10.4142(6) ?, c = 18.0973(18) ?, β = 106.0° and the structure was refined to an R-factor of 0.0446. The ketenedithioacetal functionality present between the carbonyl groups prevents the possibility of keto-enol tautomerization in these compounds. In both the crystal structures, the crystal packing is stabilized by C–H···O hydrogen bonds as well as van der Waals interactions.     

The Crystal Structures of (Z)-Ethyl 2-(4-chlorophenyl)-3-(2,4-difluorophenyl-amino)acrylate and its Analogues

Abstract  

The title compound, C₁₇H₁₄ClF₂NO₂, crystallizes in monoclinic space group P2₁/c with unit cell dimension of a = 16.276(3) ?, b = 7.5030(15) ?, c = 13.812(3) ?, α = 90°, β = 111.11(3)°, γ = 90° and Z = 4. The structure of the title compound reveals a Z configuration with respect to the C=C double bond in aminoacrylate fragment. The molecule is stabilized by intramolecular N–H···F and N–H···O hydrogen bonds. In the ethyl 2-aryl-3-arylaminoacrylates, electronic properties of the substituents in the aniline motif clearly affected the attached C–N bond length, and such effect is very little relative to Z-/E-configuration with respect to the C=C double bond.     

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 N-(4-butyryl-3-hydroxyphenyl)acetamide Monohydrate and 4-(4-Chlorophenyl)-2-methyl-4-oxobutanoic Acid: Possibilities of Yang Photocyclization

Abstract  

N-(4-butyryl-3-hydroxyphenyl)acetamide monohydrate, (I), and 4-(4-chlorophenyl)-2-methyl-4-oxobutanoic acid, (II), are photochemically inert, which is a result of their conformation. The geometrical parameters describing the molecular conformation and possibilities of the Yang photocyclization in crystals have been calculated and discussed. Compound (I) forms double ribbons along the a axis, stabilized by hydrogen bonds and π⋯π interactions. Compound (II) forms dimers. (I): triclinic, space group \textP[`1] {\text{P}}\bar{1} , a = 6.9291(12) ?, b = 7.5736(16) ?, c = 13.0528(18) ?, α = 79.643(17)°, β = 85.818(15)°, γ = 63.97(2)°, Z = 2. (II): monoclinic, space group P2₁/c, a = 11.904(2) ?, b = 9.6508(12) ?, c = 10.666(2) ?, β = 110.64(2)°, Z = 4.     

Synthesis,X-Ray Crystal Structure and Spectroscopic Properties of 1,2,3,4-Tetrahydro-2-(thenyl)-3-(<Emphasis Type="Italic">N</Emphasis>-thenylidine)-4-oxoquinazoline

Abstract  

The Schiff base formed between anthraniloyl hydrazide and thiophen-2-aldehyde is synthesized. Reaction of this Schiff base with VOSO₄ in methanol at room temperature does not yield the expected vanadium complex; instead, the Schiff base is transformed to 1,2,3,4-tetrahydro-2-(thenyl)-3-(N-thenylidine)-4-oxoquinazoline, which has been characterized by elemental analyses and by LC–MS, i.r., n.m.r. and electronic spectroscopies. The X-ray crystal structure of the quinazoline product is reported. The compound crystallizes with monoclinic (P2₁/n) space group, and the cell parameters are: a = 5.9442(7) ?, b = 13.6357(15) ?, c = 19.455(2) ?, β = 90.499(2)°. The oxo-quinazoline product is found to be luminescent when excited at its lowest energy transition.     

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 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.     

The Synthesis and Crystal Structure of New Bis(3-chlorophenyl)-[5-methyl-1-(4-methylphenyl)-1,2,3-triazol-4-yl]-methanol

Abstract  The title compound bis(3-chlorophenyl)-[5-methyl-1-(4-methylphenyl)-1,2,3-triazol-4-yl]-methanol 8 has been synthesized and established by H NMR, IR and MS spectra and X-ray diffraction crystallography. Compound 8, C₂₃H₂₉Cl₂N₃O, Mr = 424.31, crystallizes in the monoclinic space group P2₁/c with unit cell parameters a = 14.5402(6) ?, b = 12.5888(5) ?, c = 11.6510(5) ?, α = 90o, β = 100.183o(2), γ = 90o, V = 2099.05(15) ?³, D_x = 1.343 mg m⁻³ and Z = 4. The final R was 0.0514. The molecular conformation and packing is stabilized by interactions of intermolecular O1–H1···N3′. Index Abstract  The structure of bis(3-chlorophenyl)-[5-methyl-1-(4-methylphenyl)-1,2,3-triazol-4-yl]-methanol by the reaction of compound 4 and Grignard regent is studied.      

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 and Crystal Structure of (<Emphasis Type="Italic">S</Emphasis>)-2-((<Emphasis Type="Italic">S</Emphasis>)-2-(<Emphasis Type="Italic">N</Emphasis>-Ts-Amino)-3-methylbutanoyl)-3-(1H-indol-3-yl)-6-phenyl-3,4-dihydro-1,2,4-triazin-5(2H)-one

Abstract  

The diastereoselective synthesis, NMR and X-ray structure of (S)-2-((S)-2-(N-Ts-amino)-3-methylbutanoyl)-3-(1H-indol-3-yl)-6-phenyl-3,4-dihydro-1,2,4-triazin-5(2H)-one—a potential antivirus agent are reported. The compound crystallizes in the triclinic space group P1 with unit cell parameters: a = 5.9259(6) ?, b = 9.6370(12) ?, c = 12.9541(9) ?, α = 109.210(9)°, β = 90.804(7)°, γ = 105.074(10)° and Z = 1.     

Synthesis,Structure, and Two Polymorphs of 4-((1,3-Dioxoisoindolin-2-yl)methyl)-1-methoxypyridinium tetrafluoroborate

Abstract  

4-((1,3-Dioxoisoindolin-2-yl)methyl)-1-methoxypyridinium tetrafluoroborate, C₁₅H₁₃BF₄N₂O₃, 1, was obtained by alkylation of the corresponding N-oxide and has been characterized by ¹H and ¹³C NMR, IR, UV spectroscopy and by X-ray crystallography. The crystal undergoes a reversible phase transition between 173 and 293 K. At room temperature, crystals are orthorhombic, space group Pna2₁ with a = 7.2487(3) ?, b = 17.8359 (8) ?, c = 12.4077(6) ?, V = 1604.16(12) ?³, and Z = 4. At 173 K, cations adopt four conformations in monoclinic space group Cc with a = 24.7076(29) ?, b = 14.4145(9) ?, c = 21.8765(25) ?, β = 126.249(17)°, V = 6283.3(7) ?³, and Z = 16. The compound is photostable in the crystal and does not undergo homolytic N–O bond cleavage as observed in solution.     

The Synthesis and Crystal Determination of 3-Hydroxy-4-(4-methoxyphenyl)-5-(2-nitrophenyl)furan-2(5H)-one

Abstract  

The title compound, C₁₇H₁₃NO₆, was synthesized and structurally characterized by elemental analysis, MS, ¹H NMR and single crystal X-ray diffraction. It crystallizes in monoclinic system space group C 2/c with a = 27.981(6) ?, b = 12.996(3) ?, c = 8.0900(16) ?, β = 91.06(3)°, V = 2941.4(10) ?³, Z = 8, R ₁ = 0.0675, wR ₂ = 0.1626, and T = 298(2) K. The X-ray structure determination revealed that the center furanone ring is nearly coplanar with p-methoxybenzene ring and forms a dihedral angle of 87.2(1)° with the nitrobenzene ring. O–H···O Intermolecular hydrogen bonds link pairs of molecules into centrosymmetric dimers, making a graph set motif of R ₂²(10). The dimers are further assembled into a chain of edge-fused R ₄⁴(34) rings running along the [001] direction. The final three-dimensional supramolecular architecture is stabilized by weak π–π interactions.     

Synthesis and Crystal Structure of 2,4-Diiodo-6-[(2-morpholin-4-yl-ethylimino)-methyl]-phenolato-zinc(II)

Abstract  

One new complex, 2,4-Diiodo-6-[(2-morpholin-4-yl-ethylimino)- methyl]- phenolato-zinc(II) has been designed and synthesized. The structure was determined by UV, IR and single X-ray crystallography study. The title complex C₂₆H₃₀O₄N₄I₄Zn crystallizes in the triclinic space group P − 1 with the cell parameters a = 9.938(2) ?, b = 11.937(2) ?, c = 14.527(3) ?, α = 87.14(3)°, β = 79.03(3)°, γ = 76.20(3)°, V = 1565.1(5) ?³ and Z = 2. The central zinc(II) is four coordinate and bonds to two nitrogen atoms and two oxygen atoms from two 3,5-diiodosalicylaldehyde-2- morpholinoethylamine Schiff bases. The complex is linked into a column by weak intermolecular interactions.     

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, Crystal Structure and Conformational Studies of Schiff-Base Compound 2-{[4-(Phenyldiazenyl)Phenyl]Iminomethyl}-5-Bromophenol

Abstract  

Schiff-base compound 2-{[4-(Phenyldiazenyl)phenyl]iminomethyl}-5-bromo phenol (1), containing an azo group was synthesized from the reaction of p-aminoazobenzene with 5-bromosalicylaldehyde and characterized by elemental analyses, FT-IR spectroscopy and X-ray single-crystal diffraction analysis. Molecular orbital calculation has been carried out using density functional method (B3LYP) at 6-31G basis set. Compound 1 crystallizes in the orthorhombic system, space group Pca2₁, with a = 12.1781(2) ?, b = 4.4894(10) ?, c = 27.7841(5) ?, V = 1519.02(5) ?³, and Z = 4. Compound 1 displays a trans configuration with respect to the C=N and N=N double bonds.     

1-Phenyldiazenyl-8-Phenylhydrazononaphthalene-7(8H)-One-2-ol: Co-Existence of Azo-Hydroxy and Hydrazo-Keto Forms

Abstract  

The compound crystallizes in the triclinic P[`1] P\bar{1} space group and unit cell dimensions of a = 8.158 ?, b = 12.490 ?, c = 17.129 ?; α = 93.24°, β = 94.72°, γ = 97.61° and Z = 4. The structure was solved by direct methods and refined to an R1 value of 0.0890 on 2,278 observed reflections. There are two molecules in the asymmetric residue unit of the compound. In the title compound C₂₂H₁₆N₄O₂, two diazene groups at C1 and C8 and two hydroxy groups at C2 and C7 bring into play a unique azo-hydrazo equilibrium in which azo-hydroxy and hydrazo-keto forms co-exist in the molecule. The hydrazone H atom and the keto O atom are linked by an intramolecular N–H···O hydrogen bond on the other hand the hydroxy H atom and the azo N atom are linked by two intramolecular O–H···N hydrogen bonds.     

Structural Conformation of a Novel 1-Benzhydrylpiperazine Derivative: 1-Benzhydryl-4-(toluene-4-sulfonyl)-piperazine

Abstract  The title compound 1-benzhydryl-4-(toluene-4-sulfonyl)-piperazine was synthesized and the structure was investigated by X-ray crystallography. The title compound, C₂₄H₂₆N₂O₂S crystallizes in the monoclinic crystal class in the space group P2₁/c with cell parameters a = 13.5800(10) ?, b = 8.9630(7) ?, c = 18.9040(10) ?, β = 106.851(3)°, Z = 4 and V = 2202.1(3) ?³. The structure has been solved by direct methods and refined to R ₁ = 0.0468 for 3174 observed reflections I > 2σ(I). The structure reveals that the piperazine ring is in a chair conformation. The geometry around the S atom is a distorted tetrahedron. Graphical Abstract  The title compound 1-benzhydryl-4-(toluene-4-sulfonyl)-piperazine was synthesized and the structure was investigated by X-ray crystallography. The title compound, C₂₄H₂₆N₂O₂S crystallizes in the monoclinic crystal class in the space group P2₁/c with cell parameters a = 13.5800(10) ?, b = 8.9630(7) ?, c = 18.9040(10) ?, β = 106.851(3)°, Z = 4 and V = 2202.1(3) ?³. The structure has been solved by direct methods and refined to R ₁ = 0.0468 for 3174 observed reflections I > 2σ(I). The structure reveals that the piperazine ring is in a chair conformation. The geometry around the S atom is a distorted tetrahedron.

Crystal Structure of 2-(2,2-Dibromovinyl)-1-methyl-1<Emphasis Type="Italic">H</Emphasis>-imidazole-4,5-dicarbonitrile

Abstract  

The crystal structure of 2-(2,2-dibromovinyl)-1-methyl-1H-imidazole-4,5-dicarbonitrile (C₈H₄Br₂N₄, Mr = 315.92) has been determined by single crystal X-ray diffraction analysis. The compound crystallizes in the monoclinic crystal system with space group P2₁/c and unit cell parameters: a = 15.144(2), b = 16.382(3), c = 8.267(1) ?, β = 95.76(2)^o and Z = 8. The final reliability index is 0.0297 for 2505 observed reflections. The two molecules of 2-(2,2-dibromovinyl)-4,5-dicyano-1-methylimidazole are localized in independent part of unit cell. The crystal packing is stabilized by C–H···N hydrogen bonds and Br···N intermolecular interactions.     

Crystal and Molecular Structure of the 1:2 Salt Formed Between 1,2-(4-Pyridyl)Ethane and 2-(4-Hydroxyphenylazo)Benzoic Acid

Abstract  Proton transfer occurred during co-crystallization of 1,2-(4-pyridyl)ethane with 2-(4-hydroxyphenylazo)benzoic acid to yield a salt comprising a 1:2 ratio of 1,2-bis(4-pyridinium)ethane dications and 2-(4-hydroxyphenylazo)benzoate anions. Centrosymmetrically related anions associate by charge-assisted O–H···O hydrogen bonds to form 24-membered {···OC₃N₂C₄OH}₂ synthons. These are connected into a supramolecular polymer via charge-assisted N–H···O hydrogen bonds involving the 1,2-bis(4-pyridinium)ethane dications. The compound crystallizes in the triclinic space group P−1 with a = 8.517(4) ?, b = 9.110(5) ?, c = 10.477(5) ?, α = 96.850(13)°, β = 94.446(12)°, γ = 104.946(10)° and Z = 1 {two anions and a dication}. Index Abstract  Supramolecular chains mediated by charge-assisted O–H···O and N–H···O hydrogen bonding are found in the salt containing a 1:2 ratio of 1,2-bis(4-pyridinium)ethane dications and 2-(4-hydroxyphenylazo)benzoate anions.