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.     

Crystal Structure of 3,4-Dihydro-2-methoxy-2-methyl-4-phenyl-2H,5H-pyrano[3,2-c]chromen-2-one

Crystallography Reports - A new polymorph of 3,4-dihydro-2-methoxy-2-methyl-4-phenyl-2H,5H-pyrano[3,2-c]chromen-2-one (pyranocoumarin) was studied by X-ray diffraction. The crystallographic...     

Crystal Structure of Ethyl (2Z, 5R)-2-benzylidene-7-methyl-3-oxo-5-phenyl-2,3-dihydro-5H-[1,3] Thiazolo [3,2-a] Pyrimidine-6-carboxylate

Abstract  

The title compound, C₂₃H₂₀N₂O₃S, (I), crystallizes in the orthorhombic space group, Pna 2 ₁ , with cell parameters a = 18.7975(6), b = 12.5173(4), c = 8.4804(3) Å, Z = 4. The molecular structure consists of a central pyrimidine ring which is significantly puckered to assume a screw-boat conformation fused to a thiazole ring with benzyl, carboxylate, methyl, phenyl and oxy groups bonded around this fused-ring moiety. The dihedral angle between the mean planes of the thiazole, benzyl and phenyl groups and the mean plane of the pyrimidine ring is 6.1(4)°, 83.8(7)° and 6.8(4)°, respectively. The dihedral angle between the mean planes of the benzyl and phenyl rings is 88.3(5)° while between the mean planes of the phenyl and thiazole groups measures 12.6(6)°. In the absence of expected hydrogen bonding interactions, the crystal packing is influenced by a collective action of strong intramolecular C–H···S hydrogen bond interactions, close C–H···O intramolecular contacts and O–Cg π-ring interactions. A DFT molecular orbital calculation gives support to these observations.     

Crystal structure of 3-phenyl-7-bromoisoxazolo[4,5-d]pyridazin-4(5H)-one

The crystal and molecular structure of 3-phenyl-7-bromoisoxazolo[4,5-d]-pyridazin-4(5H-one, C₁₁H₆BrN₃O₂, has been determined from two- and three-dimensional X-ray data and refined by Fourier and least-squares methods toR = 0·101 for 1187 observed reflexions. Crystals of 3-phenyl-7-bromoisoxazolo-[4, 5-d]pyridazin-4(5H)-one are monoclinic:a = 7·67,b = 6·84,c = 20·52 Å, = 91·5 °,Z = 4, space groupP2₁/c. The benzene ring makes an angle of 4·5 ° with the plane of the isoxazole ring, and the other part of the molecule is slightly non-planar. The bond distances and angles compare well with those of other similar molecules. Two N-H...O hydrogen bonds join the two molecules related by a centre of symmetry. Close molecular packing is found in layers parallel to (100).     

Synthesis and crystal structure of 1-phenyl-3-methylthio-4-imino-5-allyl-pyrazolo[3,4-d]pyrimidine

The title compound 1-phenyl-3-methylthio-4-imino-5-allyl-pyrazolo[3,4-d]pyrimidine, C₁₅H₁₅N₅S, has been synthesized and characterized by x-ray diffraction: orthorhombic, space group Pbca, with a = 17.3480(9), b = 8.5022(5), c = 19.8132(11) Å. Z = 8, V = 2922.4(3) ų. The compound shows a fully delocalized pyrazolo[3,4-d]pyrimidine system with a sp² hybridization of the N(4) atom.     

Synthesis and crystal structure of 2-propyl-5-phenyl-1, 4-dioxo-1,2,3,4,5,6,7,8-octahydro-[1,4,2]diazaphosphorino [1,2-a][1,3,2]benzodiazaphosphorine 3-oxide

The synthesis and structure characterization of 2-propyl-5-phenyl-1,4-dioxo-1,2,3,4,5, 6,7,8-octahydro-[1,4,2]diazaphosphorino[1,2-a][1,3,2]benzodiazaphosphorine 3-oxide are described. The title compound has been designed to incorporate proximate carbonyl and phosphoryl groups in a heterocycle fused to benzophosphadiamide heterocycle. Crystal data: C₁₉H₂₀N₃O₃P, Monoclinic, space group P2(1)/c, with a = 9.7585(9) Å, b = 21.4319(19) Å, c = 17.7900(16) Å, β = 100.823(2)°, Z = 8, V = 3654.5(6) ų. The crystal structure shows that the proximate carbonyl and phosphoryl groups are not coplanar, and the [1,4,2]diazaphosphorino moiety prefers the boat conformation.     

Synthesis and crystal structure of 5-amino-4-cyano-1-[(5-methyl-1-t-butyl-4-pyrazolyl)carbonyl]-3-methylthio-1H-pyrazole

The title compound, 5-amino-4-cyano-1-[(5-methyl-1-t-butyl-4-pyrazolyl)carbonyl]-3-methylthio-1H-pyrazole 5, was synthesized by the treatment of 4 (5-methyl-1-t-butylpyrazole-4-carbohydrazide) with 2-cyano-3, 3-dimethylthio-acrylonitrile, and its crystal structure was determined by X-ray diffraction method. The crystal belongs to monoclinic, space group P2₁/c with unit cell parameters a = 13.566(4) Å, b = 10.833(3) Å, c = 11.202(3) Å, α = 90°, β = 98.073(5)°, γ = 90°, V = 1629.9(8) ų, Z = 4, D _c = 1.298, M _r = 318.40, μ = 0.210 mm⁻¹, F(000) = 672, R ₁ = 0.0488 and wR ₂ = 0.1250.     

The structure of 2-phenylperhydro-1,2-oxazolo[3,2-c] [1,4]oxazine

The title compound crystallizes in the monoclinic space group P2₁/n, witha=9.590(6),b=11.574(2),c=9.609(2) Å, =105.72(3)^o andZ=4. The structure was solved by direct methods and refined by full matrix least squares methods toR=0.039 for 1899 observed reflections. The stereochemistry of this 6/5 ring system is found to becis-fused with C(3)–C(4) bond in the axial and N(9)–O(1) bond in equatorial disposition. The six-membered ring in the molecule is in the chair and the five-membered isoxazolidine ring adopts an envelope conformation.     

Synthesis and crystal structure of 4,5-dibromo[2.1.1]triblattene

Reaction of 4-bromopentacyclo[7.3.0.0^2,7.0^3,11.0^6,10]dodec-11-ene (1) with Br₂—CCl₄ afforded 4,4,5-tribromopentacyclo[7.3.0.0^2,7.0^3,11.0^6,10]dodecane (2) in 89–94% yield. Subsequent treatment of 2 with KOt-Bu-t-BuOH resulted in competitive elimination of the elements of HBr and of Br₂ with concomitant formation of 4,5-dibromopentacyclo[7.3.0.0^2,7.0^3,11.0^6,10]dodec-11-ene (3, 76%) and 1 (17%), respectively. The structure of 3 was established unequivocally via application of X-ray crystallographic methods. Crystal data for 3: monoclinic, C2/c, a = 9.895(1), b = 9.0963(7), c = 12.471(1) Å, = 106.875(8)°, z = 4.     

The synthesis and crystal structure of 2-[4(S)-4,5-dihydro-4-phenyl-2-oxazolinyl]-benzenamine, and 2-[4(S)-4,5-dihydro-4-benzyl-2-oxazolinyl]-benzenamine

Two oxazolines compound 1a and 1b, 2-[4(S)-4,5-dihydro-4-phenyl-2-ozazolinyl-benzenamine, and (C₁₅H₁₄N₂O), 2-[4(S)-4,5-dihydro-4-benzyl-2-ozazolinyl-benzenamine (C₁₆H₁₆N₂O) were obtained in moderate yield from the reactions of 2-aminobenzonitrile with optically active L-(+)-Phenylglycinol and L-(+)-Phenylalaninol, respectively, in chlorobenzene under dry, anaerobic conditions. ZnCl₂ was dried under vacuum and acted as a Lewis acid catalyst in this reaction. The structures of 1a and 1b were determined by X-ray diffraction and NMR. There exist intra- and intermolecular N-H…N hydrogen bonds in the crystal structure.     

Synthesis and structure of 1-(2-amino)phenyl-2-phenyl-12H-indolo[3,2-c]carbazole ethylacetate solvate,a new indolocarbazole compound

The structure of a new indolo-carbazole compound, unique in having two indole rings with NH groupstrans-fused to a phenyl ring, has been determined by X-ray crystallography. The crystals are monoclinic, space groupP2₁/n,a=25.548(7),b=8.532(3),c=12.594(4) Å,=93.50(2)°,V _c=2740.1(2) ų,Z=4,D _k=1.240 g cm^–3, (CuK)=1.54178 Å,=5.79 cm^–1,F(000)=1080,R=0.071,R _w=0.080 for 2939 unique significant reflections measured at 298 K. The crystals retain one mole of ethyl acetate per molecule, which shows disorder. Restricted rotation of the phenyl and aminophenyl groups was detected by¹³C nmr. The title Indolo-carbazoles are easily obtained by reaction of 3-bromoindoles with 2,3-biindolyls and show an interesting planar structure which could be investigated for anticancer properties.     

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,characterization, single crystal X-ray diffraction and DFT studies of ethyl 5-methyl-1-phenyl-1H-pyrazole-4-carboxylate

The present study describes the synthesis, spectroscopic, and single crystal X-ray structural analysis of ethyl 5-methyl-1-phenyl-1H-pyrazole-4-carboxylate. The pyrazole ester of formula [C₁₃H₁₄N₂O₂] was prepared from the three-component one-pot condensation reaction of ethyl acetoacetate, N,N-dimethyldimethoxymethanamine, and phenyl hydrazine. The product was crystallized by using ethanol as solvent. The structure of the compound was confirmed by elemental analysis, Fourier transforms infrared (IR), thermogravimetric analysis, UV-visible (UV-Vis), ¹H NMR, and single-crystal X-ray diffraction studies. The gas-phase molecular geometry and the electronic structure-property of the molecule were calculated at the density functional theory. The frontier molecular orbitals, theoretical UV-Vis, and IR stretching vibrations were also reported. The compound crystallizes in the monoclinic system with the space group P2₁/c and Z = 4. The unit cell parameters are a = 12.141(3) Å, b = 13.934(4) Å, c = 7.2777(18) Å, and β = 97.816(14)⁰. The structure is stabilized by an intermolecular interaction of type C-H···O and the structure also involves C-H···π interactions.     

The crystal structure of 1-phenyl-3-methyl-4(salicylaldehyde hydrazone)-propenylidene-5-pyrazolone

The crystal structure of 1-phenyl-3-methyl-4-(salicylaldehyde hydrazone)-propenylidene-5-pyrazolone (PMPP-SH) was characterized by the single-crystal X-ray diffraction method. The cell parameters of PMPP-SH in the monoclinic P2₁/c space group are a = 10.851(1) Å, b = 11.679 (1) Å, c = 14.043 (2) Å and β = 91.89 (1)^∘. Analyzing the molecular structure suggest that, in the solid state, the title compound exists mainly in enaminopyrazolone form, which is stabilized by intramolecular hydrogen bonding, rather than NH-form.     

Molecular structure of isopropyl 1-phenyl-4-phenylhydrazono-5-oxo-3-pyrazolecarboxylate

The new azopyrazolone dye has been synthesized and its crystal structure has been investigated. Crystals of C₁₉H₁₈N₄O₃ are triclinic: ,a=7.484(1),b=10.646 (1),c=11.897(1) Å, =82.28(1), =72.86(1), =86.83(1)°,Z=2. The structure has been solved by direct methods and refined by full-matrix least-squares techniques toR=0.050 for 2622 unique reflections. The tautomeric form of the molecules has been determined as a hydrazo form. Delocalization of the C5=O3 and C4=N3 -electrons and delocalization of the lone-pair electrons of N1, N3, and N4 atoms has been observed. The intramolecular N–H...O hydrogen bond forms the six-membered ring C₂N₂H...O condensed with the pyrazolone ring. The molecules are connected by intramolecular C–H...O hydrogen bonds.     

Synthesis and crystal structure of 3-[2-oxo-2-(4-methyloxyphenylsulfonamidophenyl)ethylidene]-3,4-dihydro-1H-quinoxalin-2-one

3-[2-Oxo-2-(4-methyloxyphenylsulfonamidophenyl)ethylidene]-3,4-dihydro-1H-quinox-alin-2-one (4) was synthesized and characterized by ¹H NMR,¹³C NMR, IR, and single-crystal X-ray diffraction techniques. The crystallographic results show that the composition of the title compound is C₂₃H₁₉N₃O₅S. It belongs to triclinic crystal system and P-1 space group, with a=7.273(6) ?, b=9.092(7) ?, c=15.928(13) ?; α=85.135(11)°, β=78.297(10)°, γ=84.619(11)°, V=1024.4(14) ?³, Z=2, D _c=1.457 mg/m³, μ = 0.201 mm⁻¹, F(000)=468, R=0.0597, wR=0.1438. Supplementary material CCDC-281953 contains the supplementary crystallographic data for this paper. These data can be obtained free of charge at www.ccdc.cam.ac.uk/retrieving.html or from the Cambridge Crystallographic Data Centre, 12 Union Road, Cambridge CB2 1EZ, UK; fax: +44-1223-336033; e-mail: deposit@ccdc.cam.ac.uk.