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.     

Synthesis,Characterization, Crystal and Molecular Structure Analysis of 2,6-Dimethyl-3-Acetyl-5-Carbomethoxy-4-Phenyl-1,4-Dihydropyridine

Abstract  

The synthesis of a novel unsymmetrical dihydropyridine, bearing carboxy methyl and carbomethoxy groups at C(3) and C(5), respectively, has been achieved by applying the modified Hantzsch-type condensation, which involves the Michael addition of Knoevenagel adduct with an enamine. The product obtained was characterized by spectroscopic techniques and finally confirmed by X-ray diffraction studies. The title compound C₁₇H₁₉NO₃ crystallizes in Monoclinic crystal class in space group P2₁/c with cell parameters a = 9.9130(12) ?, b = 7.3320(5) ?, c = 22.018(3) ?, β = 109.637(3)°, V = 1507.2(3) ?³ and Z = 4. The final residual factor R ₁ = 0.0642. The structure exhibits both intra and inter-molecular hydrogen bonding of the type C–H···O and N–H···O. The pyridine ring gives boat conformation.     

Synthesis and Crystal Structure of Heptyl 3-(3,4-dihydroxyphenyl)-2-propenoate

Abstract  The title compound, C₁₆H₂₂O₄, synthesized by modified Knoevenagel condensation of protocatechualdehyde with monoheptyl-malonate and recrystallized from benzene, was confirmed by single-crystal X-ray diffraction (CCDC 272827). The compound crystallizes in triclinic space group Pī with cell parameters a = 5.296(3) ?, b = 10.711(13) ?, c = 13.870(4) ?, α = 98.84(7)°, β = 90.97(4)°, γ = 96.77(7)° and Z = 2. The structure is the E isomer and its packing is stabilized by intermolecular O–H···O and C–H···O hydrogen bonds. Index Abstract  The title compound, C₁₆H₂₂O₄, synthesized by modified Knoevenagel condensation, was confirmed by single-crystal X-ray diffraction showing its structure is in E isomer and its packing is stabilized by hydrogen bonds.      

Synthesis,Characterization and Crystal Structure of (<Emphasis Type="Italic">S</Emphasis>)-2-(2-Hydroxynaphthalen-6-yl)-<Emphasis Type="Italic">N</Emphasis>-((pyridin-4-yl)methyl) Propanamide

Abstract  

The synthesis, characterization and crystal structure of the title compound, (S)-2-(2-hydroxynaphthalen-6-yl)-N-((pyridin-4-yl)methyl) propanamide, is described. The salt is enantiomerically pure and crystallize in the orthorhombic P2₁2₁2₁ chiral space group with a = 7.9174(13) ?, b = 11.1583(18) ?, c = 11.2600(18) ?. Each molecule is linked to four neighboring molecules through the O–H···O and N–H···N hydrogen bonds into a supramolecular helical chain. The O–H···O and N–H···N hydrogen bonds lead to 24-membered open rings. Chains are further connected into layers via extensive interchain H···O and H···C short contacts.     

Supramolecular Aggregation in the 1:1 Co-crystal Formed Between Merocyanine Dye and 3-Nitrophenol,Characterized as a Hydrate

Abstract  The title organic salt comprises a (E)-4-[2-(4-hydroxyphenyl)vinyl]-1-methylpyridinium cation, a 3-nitro-phenoxide anion and a solvent water molecule of crystallisation. The anions and water molecules aggregate to form supramolecular chains facilitated by charge-assisted O–H···O hydrogen bonds and these form layers which are interspersed by layers of cations. Interactions between layers include O–H···O hydrogen bonding, as well as C–H···O and C–H···π contacts; π···π and C–H···O contacts are found within layers of cations. The compound crystallizes in the monoclinic space group P2₁/n with a = 15.018(7) ?, b = 7.328(2) ?, c = 17.571(7) ?, β = 112.342(15)°, and Z = 4. Index Abstract  A layer structure comprising alternating anions/water molecules and cations associated via charge-assisted O–H···O hydrogen bonding as well as C–H···O, C–H···π and π···π contacts is found in (II) .     

Crystal Structure of 3β-Hydroxy-16α-methylpregn-5-en-20-one

Abstract  

The crystal structure of the title compound, 3β-hydroxy-16α-methylpregn-5-en-20-one, C₂₂H₃₄O₂, was determined by direct methods using single crystal X-ray diffraction data. The compound crystallizes in the triclinic space group P1 with unit-cell parameters: a = 6.235(1) ?, b = 6.282(1) ?, c = 12.877(3) ?, α = 96.672(4)°, β = 98.746(4)°, γ = 106.838(4)°, Z = 1. The structure was refined by full-matrix least-squares to R = 0.0573 for 2,196 observed reflections. Rings A and C of the compound are in chair conformation whereas ring B is in half-chair conformation. Ring D is in envelope conformation. The A/B ring junction is quasi-trans, while ring systems B/C and C/D are trans fused about the C8–C9 and C13–C14 bonds, respectively. The steroid nucleus has a small twist, as shown by the C19–C10···C13–C18 pseudo-torsion angle of 8.0°. Molecules are connected via C–H···O hydrogen bonds to form straight chains along the c-axis of the unit cell. The straight chains are packed together to form layers.     

Crystallographic and Conformational Analysis of [(<Emphasis Type="Italic">E</Emphasis>)-2-[(3-Chlorophenylimino)methy])-4-methoxyphenol]

Abstract  The crystal structure of C₁₄H₁₂ClNO₂ was determined by X-ray analysis. It crystallizes in the triclinic space group Pc with a = 12.5346(10) ?, b = 4.5101(3) ?, c = 12.0534(11) ?, α = 90.00o, β = 113.669(6)o, γ = 90.00o, Z = 2, Dx = 1.393 mg/m³, μ (MoK_α) = 0.298 mm⁻¹. The title compound is photochromic and molecule is non-planar. It adopts a phenol–imine tautomeric form with a strong intramolecular O–H···N hydrogen bond and a strong intermolecular C–H···O hydrogen bond. Minimum energy conformations AM1 were calculated as a function of the three torsion angles θ1(C10–C9–N1–C8), θ2(C9–N1–C8–C1) and θ3(N1–C8–C1–C6), varied every 10°. As in the X-ray experiment results, molecule has an angle that makes it non-planar between two aromatic rings in AM1 optimized geometry. Graphical Abstract  Molecular and crystal structure of [(E)-2-[(3-chlorophenylimino)methy])-4-methoxyphenol], C₁₄H₁₂ClNO₂, 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.      

Structure and Antibacterial Activity of 3-(3,4-Dimethoxyphenyl)furan-2(5<Emphasis Type="Italic">H</Emphasis>)-ones

Abstract  

Crystalline hydrate of the title compound (5), C₁₉H₂₆N₂O₅·2(H₂O), was structurally characterized by single crystal X-ray diffraction. It crystallizes in monoclinic system space group P 21/c with a = 7.3987(7) ?, b = 17.8691(16) ?, c = 17.0022(13) ?, β = 112.944(3)°, V = 2070.0(3) ?³, Z = 4, R ₁ = 0.0592, wR ₂ = 0.1016, and T = 298(2) K. The X-ray structure determination revealed that the center furanone ring is nearly coplanar with 3,4-dimethoxybenzene ring, making a dihedral angle of 0.860(69)°. Two kinds of centrosymmetric tetramers characterized by graph-set motifs of R ₇⁸(36) and R ₄⁶(32) are formed through O–H···O, O–H···N and C–H···O hydrogen bonding interactions, which generate a sheet of edge-fused rings parallel to the (011) plane. These sheets are further linked into a three dimensional network by C–H···π interactions. Nine 3-(3,4-dimethoxyphenyl)furan-2(5H)-ones were synthesized and fully characterized by elemental analysis, MS and ¹H NMR. All of them were evaluated for antimicrobial activities against three Gram-positive organisms and a Gram-negative organism, and compound 5 was the most active against Staphylococcus aureus ATCC 25923.     

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.      

Crystal Structure?4-(2,4-Dihydroxybenzylideneamino)-5-methyl-2H-1,2,4-triazol-3(4H)-one

Abstract  

The title compound (I), 4-(2,4-dihydroxybenzlideneamino)-5-methyl-2H-1,2,4-triazol-3(4H)-one was characterized by single crystal X-ray diffraction. This crystal is monoclinic, space group P2₁/c with a = 10.1447(7) ?, b = 7.0972(3) ?, c = 14.6726(10) ?, β = 98107(5)°, V = 1045.85(11) ?³, Z = 4, D _c = 1.487 g/cm³, F ₀₀ = 488, R = 0.039 and wR = 0.1025, S = 1.003, T = 293 (2) K. The title molecule is planar: the angle between the triazole ring and benzene ring is 179.1(1)°. The crystal structure contains two intramolecular (O–H···N and C–H···O) and three intermolecular interaction (O–H···N, N–H···O, and C–H···O). In addition, there is also π–π interactions.     

3-Methyl-3a,4-Dihydro-3H-Thiochromeno[4,3-c]isoxazol

Abstract  The crystal structure of the title compound, C₁₁H₁₁NOS, was determined by an X-ray diffraction analysis. The compound crystallizes in the monoclinic space group P2₁/c with cell parameters a = 10.533(2) ?, b = 12.7826(19) ?, c = 7.6491(17) ?, β = 107.997(17)^°, V = 979.5(3) ?³ and Z = 4. The S containing heterocycle adopts a sofa conformation, whereas the 5-membered ring adopts an envelope conformation. The crystal packing is characterized by weak C–H···N contacts and π-stacking interactions. Graphical Abstract  The title compound, 3-methyl-3a,4-dihydro-3H-thiochromeno[4,3-c]isoxazol was synthesized by an 1,3 dipolar cycloaddition reaction and its crystal structure determined. Single crystal X-ray diffraction analysis reveals that the aromatic 6-membered ring is planar, whereas the ring containing the S atom adopts a sofa conformation and the 5-membered ring an envelope conformation. The methyl group is in an equatorial position.      

Synthesis,Crystal Structure and Antibacterial Activity of 5-Bromonicotinic Acid [1-(4-Chlorophenyl)methylidene]hydrazide Monohydrate Methanol Solvate

Abstract  The compound 5-bromonicotinic acid [1-(4-chlorophenyl)methylidene]hydrazide monohydrate methanol solvate, derived from the condensation reaction of 5-bromonicotinic acid hydrazide with 4-chlorobenzaldehyde in a methanol solution, was synthesized and characterized by elemental analysis, IR spectrum, ¹H NMR and X-ray single crystal determination. The compound crystallizes in the triclinic space group P − 1 with unit cell dimensions a = 6.9360(14) ?, b = 10.070(2) ?, c = 12.267(3) ?, α = 84.39(3)°, β = 86.10(3)°, γ = 80.50(3)°, V = 839.8(3) Ǻ³, Z = 2, R ₁ = 0.0724, and wR ₂ = 0.1720. X-ray structure determination reveals that the compound has a trans configuration with respect to the C=N double bond or C–N single bond. In the crystal structure, molecules are linked through intermolecular O–H···N, O–H···O, and C–H···O hydrogen bonds, forming layers parallel to the ab plane. The preliminary biological tests show that the compound has excellent antibacterial activity. Index Abstract  The compound 5-bromonicotinic acid [1-(4-chlorophenyl)methylidene]hydrazide monohydrate methanol solvate, derived from the condensation reaction of 5-bromonicotinic acid hydrazide with 4-chlorobenzaldehyde in a methanol solution, was synthesized and characterized by elemental analysis, IR spectrum, ¹H NMR and X-ray single crystal determination. The molecule of the compound has a trans configuration with respect to the C=N double bond or C–N single bond. In the crystal structure, molecules are linked through intermolecular O–H···N, O–H···O, and C–H···O hydrogen bonds, forming layers parallel to the ab plane. The preliminary biological tests show that the compound has excellent antibacterial activity.      

Crystal and Molecular Structure Studies of 1′-Benzyl-8-(4-fluorobenzyl)-8-azaspiro[bicyclo-[3.2.1]octane-3,4′-imidazolodine]-2′,5′-dione

Abstract  

The title compound, C₂₃H₂₃FN₃O₂ has been synthesized and the structure was investigated by X-ray diffraction studies. The compound crystallizes in the triclinic crystal class in the space group P[`1]P\overline{1} with cell parameters a = 9.345(2) ?, b = 10.940(3) ?, c = 11.986(4) ?, α = 72.349(6)°, β = 68.106(18)°, γ = 66.867(5)°, Z = 2 and V = 1027.8(5) ?³. The hydantoin ring adopts a planar conformation and is affected by the π conjugation. The pyrrolidine and piperidine rings in the bicyclo octane moiety adopt envelope and chair conformations respectively. The structure exhibits both inter and intramolecular hydrogen bonds of the type N–H···O, C–H···O and C–H···N. One of the oxygen atoms attached to the hydantoin ring simultaneously accepts two hydrogen bonds to form a three centered hydrogen bonding pattern.     

Synthesis and Crystal Structure of (2S,6R) Ethyl 1,2,6-triphenyl-4-(phenylamino)-1,2,5,6-tetrahydropyridine-3-carboxylate

Abstract  

The title compound, (2S,6R), Ethyl 1,2,6-triphenyl-4-(phenylamino)-1,2,5,6-tetrahydropyridine-3-carboxylate (C₃₂H₃₀N₂O₂), was synthesised by the reaction of benzaldehyde, aniline and ethylacetoacetate, in the presence of l (−) proline–Fe(III) complex, formed in situ, at room temperature. The compound was characterized by spectral methods and X-ray diffraction studies. The compound crystallizes in the triclinic space group P − 1 with the following unit-cell parameters: a = 9.651(4), b = 10.909(5), c = 13.737(7) ?, α = 106.597(7), β = 108.664(8), γ = 99.779(6)°, Z = 2. The crystal structure was solved by direct methods using single-crystal X-ray diffraction data collected at 100 K and refined by full-matrix least-squares procedures to a final R-value of 0.0633 for 3415 observed reflections. The 1,2,5,6-tetrahydropyridine ring exhibits a flat boat conformation. The structure has intra- and intermolecular hydrogen bonds of the type N–H···O, C–H···O and C–H···π, which help to stabilize the crystal structure.     

Synthesis,Crystal Structure and Thermal Properties of <Emphasis Type="Italic">N</Emphasis>-Acetyl-3-(2-furyl)-5-ferrocenyl-2-pyrazoline and <Emphasis Type="Italic">N</Emphasis>-Acetyl-3-(2-thienyl)-5-ferrocenyl-2-pyrazoline

Abstract  

Two novel ferrocenyl substituted N-acetyl-2-pyrazolines, N-acetyl-3-(2-furyl)-5-ferrocenyl-2-pyrazoline (3) and N-acetyl-3-(2-thienyl)-5-ferrocenyl-2-pyrazoline (4), have been synthesized and characterized by FTIR, ¹H-NMR, ¹³C-NMR techniques, elemental analysis and X-ray structure analysis. Thermal properties of these compounds have been determined by TGA, DTA and DSC analysis. Compound 3 (C₁₉H₁₈N₂O₂Fe) crystallizes in the monoclinic space group P21/c and Z = 4, with a = 8.6970(4) ?, b = 18.4725(9) ?, c = 11.0041(5) ?, β = 110.942(3)°. Compound 4 (C₁₉H₁₈N₂OSFe) crystallizes in the orthorhombic space group Fdd2 and Z = 16, with a = 84.242(2) ?, b = 13.5416(5) ?, c = 5.9405(2) ?, β = 90°. In terms of crystal packing, each compound shows different molecular arrangement, which are stabilized by C–H···O intermolecular weak hydrogen bonds, and/or C–H···π interactions.     

Structures of two N-{2-([(5-amino-1,3,4-thiadiazol-2-yl)difluoromethyl]-4-halophenyl}acetamides

Abstract  

The compounds, N-{2-[(5-amino-1,3,4-thiadiazol-2-yl)difluoromethyl]-4-chlorophenyl}acetamide (1: X = Cl) and N-{2([(5-amino-1,3,4-thiadiazol-2-yl)difluoromethyl]-4-bromo-phenyl}acetamide (1: X = Br), are isostructural. The molecules are near ‘‘V’’ shaped with the angles between the two aromatic planes ca. 84° in each case. The various intermolecular interactions, namely N–H···O, N–H···N, N–H···F, and C–H···N hydrogen bonds and C–H···π, C–Cl···π and C–O···π interactions, generate 3-D arrays. Compound (1: X = Cl) crystallizes in the monoclinic space group P21/c with a = 16.9032(7) ?, 10.2193(4) ?, c = 7.5227(4) ?, β = 100.179(3)° and Z = 4. Compound (1: X = Br) crystallizes in the monoclinic space group P21/c with a = 17.2119(4) ?, 10.2167(2) ?, c = 7.5677(2) ?, β = 100.326(2)° and Z = 4.     

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.     

Inter- and Intra-Molecular Hydrogen Bonding in Bis(2-amino-5-fluoro-3-methylphenyl)disulfide

Abstract  Bis(2-amino-5-fluoro-3-methylphenyl)disulfide was obtained by oxidation of 2-amino-5-fluoro-3-methylbenzenethiol and was characterized by elemental analysis, IR and ¹H-NMR spectroscopy. The X-ray structure was determined. Crystal data: C₁₄H₁₄N₂F₂S₂: Monoclinic, P2₁ /n, a = 11.8268(3), b = 9.5770(3), c = 12.3977(3) ?, β = 98.079(2)°, V = 1390.29(7) ?, Z = 4. The supramolecular structure arises because the NH₂ groups form three center S···H···F hydrogen bonds and two center N–H···F and N–H···S hydrogen bonds. Index Abstract  Inter- and Intra-Molecular Hydrogen Bonding in Bis(2-amino-5-fluoro-3-methylphenyl)disulfide J. E. Drake¹, M. B. Hursthouse², M. E. Light², R. Maheshwari³, K.G. Ojha³, R. Ratnani^3* Bis(2-amino-5-fluoro-3-methylphenyl)disulfide is linked into a three-dimensional frame work by a combination of intermolecular N–H···F and N–H···N and intramolecular N–H···S hydrogen bonds. The supramolecular structure arises because the NH₂ groups form three center S···H···F hydrogen bonds and two center N–H···F and N–H···S hydrogen bonds.      

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.     

Spectroscopic Studies and Crystal Structure of 1-[(2,5-dioxopyrrolidin-1-yl)(phenyl) methyl] Thiourea

Abstract  A new mannich base 1-[(2,5-dioxopyrrolidin-1-yl)(phenyl)methyl] thiourea formed by the direct condensation of thiourea, succinimide and benzaldehyde has been synthesized. The structure of this mannich base has been elucidated on the basis of micro elemental analysis, IR, ¹H NMR, ¹³C NMR, Mass and UV–Visible Techniques. The crystal structure of the title compound C₁₂ H₁₃ N₃ O₂ S was determined. It crystallizes in the monoclinic system, space group P2₁/c with a = 10.8234 (7) ?, b = 6.0355 (5) ?, c = 19.3692 (14) ?, β = 100.540(3)°, Z = 4 and V = 1243.94 (16) ?³. The structure was solved by the full-matrix least squares on F ² and had a refined R value of 0.0465 for 1,964 observed reflections. The crystal structure is stabilized by strong intramolecular C–H···O, C–H···S interactions and inter molecular N–H···O and S···S interactions. Graphical Abstract  This paper describes the spectroscopic and crystallographic studies of the title compound which is essential in ascertaining the structure of this new compound.