Molecular and crystal structures of 2-amino-5-benzoyl-4-(2-nitrophenyl)-3-cyano-4,5-dihydrothiophene

The crystal structure of 2-amino-5-benzoyl-4-(2-nitrophenyl)-3-cyano-4,5-dihydrothiophene is determined by X-ray diffraction analysis. The unit cell parameters are as follows: a = 10.878(2) Å, b = 12.890(3) Å, c = 13.539(4) Å, α = 108.15(2)°, β = 99.26(2)°, γ = 107.13(2)°, V = 1656(2) ų, d _calcd = 1.410 g/cm³, Z = 4, and space group P1ˉ. The molecules occupy two systems of independent positions in the crystal. Similar to the compounds studied earlier in this series, the o-nitrophenyl substituent has a synperiplanar orientation relative to the hydrogen atom at the C(4) atom of the heterocycle. __________ Translated from Kristallografiya, Vol. 45, No. 2, 2000, pp. 282–285. Original Russian Text Copyright ? 2000 by Nesterov, Kuleshova, Samet, Shestopalov.     

Synthesis and X-ray structural investigations of 2-amino-7-methyl-4-(1-naphthyl)-5-oxo4H,5H-pyrano[4,3-b]pyran-3-carbonitrile and 2-amino-4-(1-naphthyl)-5-oxo-4H,5Hpyrano[3,2-c]chromene-3-carbonitrile

Synthesis and X-ray structural investigations have been carried out for the two title compounds C₂₀H₁₄N₂O₃ (4) and C₂₃H₁₄N₂O₃⋅C₂H₃N (5). Compound 4 crystallizes in the monoclinic space group P2₁/n, with a = 7.0542(5), b = 8.822(1), c = 24.833(2) ?, β = 94.30(4)^∘, V = 1541.0(4) ?³, and Z = 4. Compound 5 crystallizes with an acetonitrile solvent molecule in the monoclinic space group P2₁/n, with a = 11.075(1), b = 7.854(1), c = 22.703(2) ?, β = 90.67(1)^∘, V = 1974.5(3) ?³, and Z = 4. In both molecules, the 4H-pyran ring adopts a flattened-boat conformation. The naphthalene substituent occupies a pseudo-axial position and the dihedral angle with the flat part of the pyran ring is equal to 94.6(3) in 4 and 76.8(3)^∘ in 5. The mutual orientation of these fragments and the flatness of the heterocyclic rings lead to H⋅sH intramolecular steric interactions: H4A⋅sH18A 1.98 ? in 4 and 2.11 ? in 5. In the crystal of 4, intermolecular hydrogen bonds N–H⋅sO and C–H⋅sN link molecules into infinite tapes along the b axis. In the crystals of 5, intermolecular hydrogen bonds N–H⋅sO and C–H⋅sN link molecules into infinite layers parallel to the bc plane. In each case, the C–H⋅sN interaction can be considered to be a weak hydrogen bond. The acetonitrile molecules link via intermolecular weak C–H⋅sN hydrogen bonds to form infinite chains along the b axes.     

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.     

The hydrogen bonding in 2-amino-3-cyano-4-(3-nitrophenyl)-4,6-dihydro-5H-pyrano[3,2-c]quinolin-5-one N,N-dimethylformamide solvate monohydrate

The crystal structure of 2-amino-3-cyano-4,6-dihydro-4-(3-nitrophenyl)-5H-pyrano[3,2-c]quinolin-5-one N,N-dimethylformamide solvate monohydrate is determined by room temperature X-ray diffraction. The title compound 1, C₂₂H₂₁N₅O₆, is triclinic, space group P-1, a=9.109(2) ?, b=11.340(2) ?, c=12.485(2) ?, α=70.02(1)°, β=69.36(1)°, γ=67.32(1)°, Z=2, V=1081.4(4) ?³. It is interesting that a bridge-like hydrogen bond O–H···O is formed between the title compound and solvent molecules of water with molecular ratio of 2:2 building a bi-layer framework. In addition, there are two other types of classical hydrogen bonds N–H···N and N–H···O in the crystal structure.Supplementary material Crystallographic data for the structure reported in this paper have been deposited with the Cambridge Crystallographic Data Centre as supplementary publication no. CCDC-275001. Copies of available material can be obtained, free of charge, on application to the Director, CCDC, 12 Union Road, Cambridge CB2 1EZ, UK, (fax: +44-(0) 1223–336033 or e-mail: deposit@ccdc.cam.ac.uk).     

Synthesis and crystal structures of 5-amino-1-(2-hydroxyethyl)imidazole-4-carboxamide and 5-amino-1-(2-chloroethyl)-4-cyanoimidazole

Both 5-amino-1-(2-hydroxyethyl)imidazole-4-carboxamide (AHIC) and 5-amino-1-(2-chloroethyl)-4-cyanoimidazole (ACCI) have been synthesized and crystallized in the monoclinic space group P2₁/c, Z = 4, with a = 8.420(2), b = 9.759(2), c = 10.583(2) Å, = 111.80(2)° for AHIC and a = 6.139(1), b = 8.522(2), c = 15.156(3) Å, = 96.71(2)° for ACCI. Differences in the molecular geometries of the two compounds are attributed to the differences in the substituents at the 1- and 4-positions of the imidazole ring. The molecular conformation of AHIC is stabilized by intramolecular hydrogen bonding between the 5-amino and the vicinal carboxamide moiety, resulting in an extended planar structural pattern. The presence of the cyano group in the 4-position of ACCI prevents the formation of such an intramolecular hydrogen bond. Both the crystal structures are stabilized by networks of intermolecular hydrogen bonds.     

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 crystal structure elucidation of 1-(4-fluorobenzyl)-2-(4-cyanophenyl)-1H- benzimidazole-5-carbonitrile

The synthesis and spectral identification of 1-(4-fluorobenzyl)-2-(4-cyanophenyl)-1H-benzimidazole-5-carbonitrile (1) have been reported. IR, ¹H NMR, and EI mass spectral analysis were used for its spectral identification. The structure of 1 was confirmed by X-ray crystallographic studies. Intramolecular hydrogen bond occurs between the imidazole nitrogen and one of hydrogen of the florobenzene. The crystal packing is governed by C–HN intermolecular hydrogen bonds. The molecular structure observed in crystal and the optimised geometries at the HF level by doing semi-empirical and ab initio calculations were compared.     

Conformational polymorphism of N-(4-butoxyphenyl)-4-(4′-nitrophenyl)-2-thiazolamine

Crystallography Reports - The molecular and crystal structures of three concomitant polymorphic modifications of N-(4-butoxyphenyl)-4-(4′-nitrophenyl)-2-thiazolamine are investigated by X-ray...     

Crystal structure of 3-amino-5-acetyl-4,7-dihydro-6-methyl-4-(2-nitrophenyl)-2-cyanothieno[2,3-b]-pyridine and specific features of its molecular packing in crystal

The molecular and crystal structures of 3-amino-5-acetyl-4,7-dihydro-6-methyl-4-(2-nitrophenyl)-2-cyanothieno[2,3-b]-pyridine is determined by X-ray diffraction. The unit-cell parameters are as follows: a = 14.68(1) Å, b = 8.704(5) Å, c = 25.36(1) Å, V = 3241(6) ų, d _calcd = 1.453 g/cm³, Z = 8(1,1), and space group Pna2₁. Theo-nitrophenyl substituent is synperiplanar relative to the hydrogen atom at the C(4) atom of the heterocycle. Two crystallographically independent reference molecules A and B in the structure can be considered a pair of the enantiomers related by an approximate noncrystallographic center of inversion. The degree of approximation of this pseudocenter is discussed. It is shown that the structure can be described as a combination of two systems of translationally equal layers. The pseudosymmetry of the crystal structure and the possibility of forming a similar molecular packing with a higher crystallographic symmetry are considered.     

Design of molecules and noncentrosymmetric crystals of 3-(4-nitrophenyl)-2-phenylacrylic acid derivatives

The derivatives of 3-(4-nitrophenyl)-2-phenylacrylic acid are synthesized. It is shown that the chemical modification of this acid results in a change in the symmetry of the supramolecular fragment formed by molecules in the crystal. In turn, this change leads to a change in the crystal symmetry and favors the formation of a noncentrosymmetric crystal structure. The crystal structures of 3-(4-nitrophenyl)-2-phenylacrylic acid (I), 3-(4-nitrophenyl)-2-phenyl-triethyl aminoacrylate (II), and 3-(4-nitrophenyl)-2-phenylacrylic acid (3-methoxy)phenyl ester (III) are investigated by X-ray diffraction.     

Crystal structure of racemic 5-(p-nitrobenzoylamino)-5-methyl-4-oxo-1,3-dioxane

C₁₂H₁₂N₂O₆ crystallized from methanol in the monoclinic space group P2₁/c (Z=4) witha=13.333(4),b=10.154(3),c=9.597(2) Å and=102.37(2)°.M _r=280.24,V=1269.1(6) ų,D _x=1.466 g cm^–3,(Mo K)=0.71069 Å,=1.29 cm^–1,T=295 K. The structure was solved by direct methods and refined by full-matrix least-squares to a finalR (R _w)=0.049 (0.057) for 916 observed reflections. The molecules are linked by strong N-HO(4) hydrogen bonds with NO distance of 2.995(4) Å. The infinite racemic chains run in [001] direction.     

Synthesis and crystal structures of 2-amino-3-cyano-4-(2-chlorophenyl)-1,4-dihydro-2H-pyrano[3, 2-h]quinoline and 2-amino-3-cyano-4-(2-chlorophenyl)-8-(2-chlorobenzylidene)-1,4,5,6,7,8-hexahydrobenzo[b]pyran

The title compounds 2-amino-3-cyano-4-(2-chlorophenyl)-1,4-dihydro-2H-pyrano[3, 2-h]quinoline 1 (C₁₉H₁₂ClN₃O, M _r = 333.77) and 2-amino-3-cyano-4-(2-chlorophenyl)-8-(2-chlorobenzylidene)-1,4,5,6,7,8-hexahydrobenzo[b]pyran 2 were synthesized and crystallized. The crystals of compound 1 are triclinic, space group P-1, a = 7.488(2), b = 9.127(3), c = 12.252(3) Å, = 73.58(2), = 78.38(2)°, = 75.39(2), Z = 2, V = 769.5(4) ų; The compound 2 crystallizes in space group P2₁/n, with cell parameters a = 13.582(2), b = 8.974(1), c = 16.960(2) Å, = 103.34(1)° and D _calc = 1.352 g/cm^–3 for Z = 4. X-ray analysis reveals that atoms C(1)—C(5) and O form a pyran ring in compound 1, which adopts half-chair conformation. In compound 2 the atoms C(12)—C(16) and O form a pyran ring which adopts boat conformation, another six-membered ring (C(8)—C(13)) adopts a half-chair conformation. In addition, there are intermolecular hydrogen bonds in the crystal structures 1 and 2.     

Crystal structure of the molecular complex of 3-[1-(4-nitrophenyl)-3-oxobutyl]-4-hydroxychromen-2-one with ethanol

The crystal structure of 2,3H-2-methyl-4-(4-nitrophenyl)-5-oxobenzopyrano[3,4-e]dihydropyran-2-ol is investigated using X-ray diffraction. The unit cell contains an ethanol molecule that forms hydrogen bonds with O-H and C-O groups of two molecules of the main compound and acts as a proton donor and a proton acceptor in these hydrogen bonds. Owing to these interactions, infinite chains are formed in the crystal. The crystallographic data for the structure of C₁₉H₁₅NO₆·C₂H₅OH (M = 399.39) are as follows: the crystals are triclinic, space group P1, a = 5.5340(3) Å, b = 8.0109(4) Å, c = 11.0112(5) Å, α = 88.773(2)°, β = 84.788(2)°, γ = 79.958(2)°, and Z = 1.     

Crystal structures of difluoro[2-(4-methoxyphenyl)-3-oxo-3-phenylpropanalato]boron(III), [BF2(C16H13O3)], and bis[2-(4-methoxyphenyl)-3-oxo-3-phenylpropanalato]copper(II), [Cu(C16H13O3)2]

The crystal structures of difluoro[2-(4-methoxyphenyl)-3-oxo-3-phenylpropanalato]boron(III), [BF₂(C₁₆H₁₃O₃)], and bis[2-(4-methoxyphenyl)-3-oxo-3-phenylpropanalato]copper(II), [Cu(C₁₆H₁₃O₃)₂], have been determined by single-crystal X-ray diffraction methods. The structures were solved by direct methods and electron density calculations and were refined by the full-matrix least-squares method. Difluoro[2-(4-methoxyphenyl)-3-oxo-3-phenylpropanalato]-boron(III) crystallizes as yellow rhombs in the monoclinic space groupP2₁/c witha=11.429(3),b=11.364(4),c=11.412(4) Å,=92.19(2)°,V=1481.0(8) ų andZ=4. A total of 2754 unique reflections were collected. Of these 1342 were considered observed [I>3(I)] leading to a finalR-value of 0.045. Boron is tetrahedrally coordinated to the two fluorine atoms and to two oxygen atoms of the bidentate 2-(4-methoxyphenyl)-3-oxo-3-phenylpropanalato ligand, C₁₆H₁₃O ₃ ^– . Average bond distances: C-C (aromatic) 1.378(10) Å, B-O 1.473(7) Å and B-F 1.343(4) Å. bis[2-(4-Methoxyphenyl)-3-oxo-3-phenylpropanalato]copper(II) crystallizes as dark yellow-green plates in the monoclinic space groupC2/c witha=23.410(7),b=13.856(3),c=8.039(3) Å,=101.79(2)°,V=2553(1) ų andZ=4. Of the unique set of 3076 scanned reflections 2401 hadI>3(I) for whichR became 0.040. Copper is coordinated to four oxygen atoms, two from each of the two bidentate 2-(4-methoxyphenyl)-3-oxo-3-phenylpropanalato ligands, in a distorted square planar manner. The molecule hasC ₂ symmetry. Average bond distances: C-C (aromatic) 1.383(6) Å and Cu-O 1.896(8) Å. The crystals of both compounds consist of monomeric molecular complexes held together by van der Waals forces.     

Structure of ethyl(3-amino-5-nitrobenzo[b]thiophen)-2-carboxylate

The title compound was obtained as main product by the reaction of 3-chloro-5-nitro-1,2-benzisothiazole with diethyl malonate in sodium ethoxide. It crystallizes in the monoclinic space groupP2₁/n witha=12.143(5),b=11.172(4),c=8.567(3) Å,=95.51(2)°,Z=4. The structure was solved by direct methods and refined by full-matrix least-squares to a finalR value of 0.035 for 1217 reflections. The entire molecule is substantially planar except for the terminal methyl group. The amino group is involved in intra- and intermolecular hydrogen bonding.