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.     

5-Pyridine 4-yl-3H-(1,3,4) Oxadiazole-2 Thione Hydrochloride Monohydrate, (I), and 4 [5-Ethylsulfanyl)-(1,3,4) Thiadiazole-2-yl]-Pyridinium Perchlorate, (II)

Abstract  

The title compounds C₇H₈ClN₃O₂S, (I), and C₉H₁₀ClN₃O₄S_2, (II), both crystallize in monoclinic space group P2₁ /c with unit cell parameters (I) a = 7.9402(7), b = 10.6312(9), c = 11.7626(10), ?, β = 99.271(5)°, Z = 4 and (II) a = 5.1439(2), b = 9.0636(4), c = 27.1814 (7), ?, β = 95.116(2)°, Z = 4. In (I) the molecule consists of a 5-pyridine-4-yl group bonded to the carbon atom at the 5 position of (1, 3, 4) oxadiazole-2 thione hydrochloride monohydrate. The angle between the mean planes of the oxadiazole and pyridine rings is 9.6(6)°. Crystal packing in (I) is stabilized by strong N–H···O hydrogen bonds in concert with a solvent water molecule and weak O–H···Cl, O–H···S, N–H···Cl intermolecular interactions. The crystal structure of compound (II) consists of 4 [5-ethylsulfanyl)-(1, 3, 4) thiadiazole-2-yl]-pyridinium perchlorate, (C₉H₁₀N₃S₂)⁺(ClO₄)⁻, cation–anion pairs, containing strong intermolecular N–H···O hydrogen bonds and weak C–H···O and N–H···O intermolecular interactions operating between the ionic species that form a cooperative hydrogen-bonded, infinite chain O–H···O–H···O–H network which generates a sheet motif structure in the unit cell. It is also supported by weak intermolecular Cg···Cg π–π and Cl–O···Cg π-ring interactions which gives additional support to molecular packing stability in the unit cell. Geometry optimized MOPAC AM1 computational calculations on each compound provides support to the structural features in their respective crystal structures.     

Structural and Spectral Analysis of a Mannich Base: 3-(Morpholin-4-ylmethyl)-1,3-Benzothiazole-2-Thione

Abstract  

The crystal structure of 3-(morpholin-4-ylmethyl)-1,3-benzothiazole-2-thione, C₁₂H₁₄N₂OS₂, crystallizes in the monoclinic space group (P2₁/c). This benzothiazole derivative is a mannich base. Methylene group bridges the molecules of 2-mercapto benzothiazole and morpholine with an angle at the methylene bridge being 110.31(12)° [N–C–N]. The dihedral angle between the benzothiazole and morpholine planes is 70.37(5)°. The morpholine ring adopts a chair conformation. The molecular structure is stabilized by the weak C–H···S hydrogen bond in addition to the C–H···π and π···π interactions. Present study reports the conformation and hydrogen bonding interactions. Spectral analysis complement the structure analyzed.     

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.      

Syntheses and Crystal Structures of Two Ferrocenyl Dicarboximides

Abstract  

Reactions of 1,1′-ferrocenedicarboxylic chloride with 2-aminopyrimidine and 2-aminopyrazine produce organometallic dicarboximides I and II, respectively. They crystallize in space groups F dd2 and P2₁/c, respectively. The molecules of I lying on twofold rotation axes are linked into a B-faced sheet by a C–H···O=C hydrogen bond [H····O = 2.46, C···O = 3.163(7) ? and C–H···O = 132°]. The sheets are linked into a layered structure by two types of weak C–H···O=C hydrogen bonds [H···O = 2.71, C···O = 3.340(8) ? and C–H···O = 126°; H···O = 2.69, C···O = 3.303(10) ? and C–H···O = 124°]. The molecules of II are linked into a centrosymmetric R ₂²(12) dimer by a C–H···O hydrogen bond [H···O = 2.40, C···O = 3.321(10) ? and C–H···O = 172°]. The dimers are further packed along the a axis by a C–H···O hydrogen bond [H···O = 2.69, C···O = 3.416(9) ? and C–H···O = 135°] to give an [100] double-chain. The double-chain is packed in the [010] direction by a C–H···O=C hydrogen bond [H···O = 2.69, C···O = 3.532(9) ? and C–H···O = 150°]. Further the intermolecular C–H···N hydrogen bond involving the cyclopentadienyl group as a hydrogen-bond donor and pyrazine N atom as an acceptor [H···O = 2.71, C···N = 3.536(10) ? and C–H···N = 148°] leads to a three-dimensional framework structure.     

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.     

Ordering of the Water Molecule in the Crystal Structure of 2-[3-Methyl-4-(2,2,2-Trifluoroethoxy)-2-Pyridinyl]Methylthio-<Emphasis Type="Italic">1H</Emphasis>-Benzimidazole Hydrate (Lansoprazole Sulphide Hydrate)

Abstract  

Lansoprazole sulphide (2-[3-methyl-4-(2,2,2-trifluoroethoxy)-2-pyridinyl]methylthio-1H-benzimidazole) hydrate crystallizes in the triclinic space group P-1 with two molecules in the asymmetric part of the unit cell. The molecules are almost identical, the normal probability plots show that the differences between them are of statistical nature. The crystal structure is determined mainly by the O–H···N and N–H···O hydrogen bonds; and both symmetry independent molecules create the hydrogen-bonded structures on their own. The common motif is the C₂²(6) chain of molecules along x (A) or y (B), but the interactions between the chains are different: chains of molecules A are joined by O–H···N(pyridine) hydrogen bonds while those of molecules B– by relatively strong O–H···S hydrogen bonds. Additionally, in both cases there are also C–H···S, C–H···π and π–π interactions between the neighbouring molecules. The different intermolecular interactions might be connected with the observed disorder of water molecules in the B-chains. At room temperature the s.o.f.’s of two alternative positions refined at 0.760(17) and 0.240(17). The less-occupied water molecule does not take part in the O–H···S hydrogen bonding. When temperature decreases the importance of this interaction grows, the occupancy of less occupied position becomes smaller and finally, around 150 K the structure becomes fully ordered.     

Crystal Structure of <Emphasis Type="Italic">N</Emphasis>-(2-Pyridylmethylene)benzene-1,4-diamine

Abstract  

The crystal structure of amino containing Schiff base, N-(2-pyridylmethylene)benzene-1,4-diamine, was determined via X-ray diffraction analysis. The title compound crystallizes in orthorhombic system, space group Pc2 ₁ n, with unit cell dimensions a = 5.8945(6), b = 11.9233 (10), c = 14.5356 (16) ?, V = 1021.59 (18) ?³, Z = 4. The molecules are linked by intermolecular N–H···N hydrogen bonds to form supramolecular sheets along with the bc crystallographic plane. The crystal structure is further stabilized by C–H···π stacking interactions.     

Crystal Structure of 2-<Emphasis Type="Italic">Exo</Emphasis>-Phenyl-2,3,4,5-Tetrahydro-1,4-Epoxinafto[1,2-b]azepine

Abstract  

The title compound, C₂₀H₁₇NO, crystallizes in the orthorhombic P2₁2₁2₁ space group with unit cell parameters a = 7.6903(7) ?, b = 18.979(2) ?, c = 19.753(2) ?, with two crystallographically independent molecules in the asymmetric unit, which differ from one another in the slight rotation of the phenyl ring; this allows the formation of three internal hydrogen bonds, two of the type C–H···N and one of the type C–H···O, in one of the molecules, in contrast with only two of the type C–H···N in the other. The compound is rich in aromatic π rings and therefore the crystal packing is entirely dominated by cohesive weak C–H···π interactions among neighboring molecules producing an efficient packing with 71.2% of occupied space.     

Spectral and X-ray Diffraction Studies of <Emphasis Type="Italic">N</Emphasis>-(2-Nitrophenyl)-5-Phenyl-1,3,4-Oxadiazole-2-Amine

Abstract  

Thiosemicarbazides and their derivatives are well known for their use in biological activity and many applications in pharmaceutical and industrial fields. The cyclization of 1-benzoyl-4-(2-nitrophenyl)-3-thiosemicarbazide (BNPTSC) in dimethylformamide (DMF) medium furnished N-(2-nitrophenyl)-5-phenyl-1,3,4-oxadiazole-2-amine (NPPOA). The chemical structure of the above substituted 1,3,4-oxadiazole has been assigned by IR, mass and X-ray diffraction studies. The XRD studies reveal the presence of four types of hydrogen bonds (N–H···O, N–H···N, C–H···O, C–H···N) in the crystal packing. The crystal system was found to be orthorhombic with a space group Pca2(1) and the unit cell dimensions are: a = 26.873(3) ?, b = 6.0827(7) ?, c = 7.8502(10) ?, α = 90°, β = 90°, γ = 90° and Z = 4.     

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.     

Hydrogen Bonded 3D Supramolecular Architectures of Two Organic Salts Assembled from 2-Aminoheterocyclic Compounds and Phosphoric Acid

Abstract  

Two phosphate salts (2-aminopyrimidine): (phosphoric acid): H₂O [HL1⁺ (H₂PO₄) ⁻ ]·H₂O (1), and (4-phenylthiazol-2-amine): (phosphoric acid) [HL2⁺·(H₂PO₄)⁻] (2) based on 2-aminoheterocyclic compounds, 2-aminopyrimidine (L1), and 4-phenylthiazol-2-amine (L2) were prepared and structurally characterized by X-ray crystallography. Compound 1 crystallizes in the triclinic, space group P-1, with a = 6.2201(7) Å, b = 8.6139(9) Å, c = 9.4800(10) Å, α = 109.685(2)°, β = 106.3340(10)°, γ = 95.4450(10)°, V = 448.72(8) Å³, Z = 2. For 1, the cations were linked to each other via intermolecular C–H···N hydrogen bonds to form a 1-D chain structure running along the a-axis direction. The anions and the water molecules were connected alternatively along the a-axis direction through O–H···O hydrogen bonds to form a 1-D chain also. The cationic chains and the anionic chains were alternatively connected along the c-axis direction through N–H···O and C–H···O hydrogen bonds to form a 2D corrugated sheet. Adjacent sheets were combined together through π–π interaction to form double sheet. These double sheets were further joined together by O–H···O and N–H···O hydrogen bonds to produce a 3D network structure. Compound 2 crystallizes in the Orthorhombic, space group Pbca, with a = 10.1929(10) Å, b = 8.4406(9) Å, c = 27.589(2) Å, α = 90°, β = 90°, γ = 90°, V = 2373.6(4) Å³, Z = 8. In 2, the phosphates formed 1D chain along the b-axis through two P–O–H···O = P hydrogen bonds. The cations formed 1D zigzag chain along the b-axis direction under the CH–π interaction. The anionic chains were intercalated between two adjacent cationic chains through N–H···O, O–H···O, C–H···O, and O–S contacts. Such stacking repeated along the c-axis direction to form a 3D network structure.     

Structural Studies of Two Isoelectronic Tetrakis Isocyano Complexes

Abstract  

Two isoelectronic tetrakis isocyano compounds, tetra(p-isocyanoanisole)nickel(0) and tetra(p-isocyanoanisole)copper(I) hexafluorophosphate were synthesized from nickel bis cyclooctadiene and copper (I) tetra acetonitrile hexafluorophosphate and the isonitrile, respectively, and their structures were determined. The nickel complex crystallizes in the orthorhombic space group P2₁2₁2₁ with a = 9.6709(8), b = 15.2324(13), c = 19.0955(16) ? and Z = 4. The copper salt forms crystals with a tetragonal setting in P4/n with a = b = 15.8206(5), c = 6.5848(4) ? and Z = 2. Both complexes exhibit the approximate tetrahedral coordination environment expected for 18 valence electron complexes with soft σ-donor π-acceptor ligands. Packing in the nickel complex is dominated by weak π–π stacking, C–H···π_phenyl, and C–H···π interactions towards the isonitrile carbon and nitrogen atoms, and several slightly stronger C–H···O interactions. In the copper complex the presence of the PF₆ anion allows for the formation of stronger C–H···F interactions, and these in combination with π–π stacking and C–H···O hydrogen bonds dominate the packing.     

Synthesis and Crystal Structures of Methyl 3-(Benzoylamino)-6-methyl-2-oxo-2<Emphasis Type="Italic">H</Emphasis>-pyran-5-carboxylate and <Emphasis Type="Italic">N</Emphasis>-[5-(3,4-Dimethoxyphenyl)-6-methyl-2-oxo-2<Emphasis Type="Italic">H</Emphasis>-pyran-3-yl]benzamide

Abstract  

The compounds methyl 3-(benzoylamino)-6-methyl-2-oxo-2H-pyran-5-carboxylate (1), C₁₅H₁₃NO₅, and N-[5-(3,4-dimethoxyphenyl)-6-methyl-2-oxo-2H-pyran-3-yl]benzamide (2), C₂₁H₁₉NO₅, crystallize as a centrosymmetric hydrogen-bonded dimer facilitated by N–H···O interactions involving the amide and carbonyl moiety of the lactone group of adjacent molecules. Supramolecular aggregation in 1 is controlled by a combination of π–π interactions [centroid–centroid distance = 4.0745(11) ?] and weak C–H···O hydrogen bonding between the phenyl ring of the benzoylamino group and the carbonyl atom of the methoxycarbonyl group and in 2 by a combination of π–π interactions [centroid–centroid distance = 4.0699(8) and 4.1556(10) ?], weak C–H···O interactions between the methoxy substituents of the adjacent dimethoxyphenyl group and weak C–H··· π interactions.     

Synthesis, Spectroscopic Characterization and Crystal Structure of a New Acetyl phosphorylamidate P(O)[NHC(O)C6H4(4-NO2)][N(CH(CH3)2)(CH2C6H5)]2

Abstract  

A new acetyl phosphorylamidate P(O)[NHC(O)C₆H₄(4-NO₂)][N(CH(CH₃)₂)(CH₂C₆H₅)]₂ has been synthesized and characterized by elemental analysis, ¹H, ¹³C and ³¹P NMR, IR and single crystal X-ray diffraction. Single crystal X-ray analysis shows that it belongs to triclinic system, space group P[`1] P\bar{1} , with a = 10.5868(16) Å, b = 11.8058(18) Å, c = 12.4364(19) Å, α = 65.410(3)°, β = 67.492(4)°, γ = 85.879(3)°, V = 1,298.6(3) Å³, and Z = 2. The intermolecular PO···HN hydrogen bond makes H-bonded dimer of molecule with Ci symmetry. In the crystal network, the dimers are aggregated in the chain arrays through π-stacking between p-NO₂–C₆H₄–C(O)–NH– moieties. Moreover, weak C–H···O and C–H···π interactions exist in the crystal network.     

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 and Molecular Structure of 4-Aminobenzohydrazide

Abstract  

The molecule of 4-aminobenzohydrazide is essentially planar and geometric parameters conform to literature precedents. Supramolecular N–H···O and N–H···N interactions combine to link molecules of 4-aminobenzohydrazide into a three-dimensional network. Weaker N–H···N and N–H···π interactions consolidate the structure. The compound crystallizes in the monoclinic space group P2₁/n with a = 5.411(2) ?, b = 14.000(6) ?, c = 9.894(4) ?, β = 103.917(7)o, and Z = 4.     

Synthesis and Crystal Structure Analysis of Methyl 2-Hydroxyimino-3-phenyl-propionate

Abstract  

As precursors of α-amino acids, methyl 2-hydroxyimino-3-phenyl-propionate (F.W. 193.20) was synthesized, characterized by ¹H NMR, IR, element analysis and confirmed by X-ray crystal structure analysis. This compound crystallizes in monoclinic class under the space group P2₁/c with cell parameters, a = 8.6435(17) Å, b = 5.4957(11) Å, c = 21.146(4) Å; β = 97.12(3)°, and Z = 4. The structure exhibits inter-molecular hydrogen bonds of the type O–H···N, O–H···O, C–H···O.     

Crystal Structure and Conformation Study of 3-Methyl-2, 6-bis (4-chlorophenyl) Piperidin-4-one Thiosemicarbazone Derivative

Abstract  

The 1, 3-dipolar cycloaddition reactions with trans azomethine ylide produce spirooxindole derivatives, which are active against certain bacterial pathogens. Spirooxindole ring systems have a very important place in medicinal chemistry because they are the central skeleton for numerous alkaloids and have potential biological activity. This newly synthesized target molecule, PSSPI was crystallized and its X-ray crystal structure has been derived. The crystallographic data of PSSPI are: C₃₄H₃₈N₂O₃; M.W = 522.7, Monoclinic, P2₁/a, with cell parameters a = 11.959(6) ?, b = 19.308(3) ?, c = 13.452(6) ?, β = 107.81(4)°; V = 2957(2) ?³, Z = 4, D _cal = 1.174 mg/m³, λ (Mo K _α ) = 0.71073 ?. Based on the crystal structure, the piperidine, pyrrolidine and cyclohexanone rings adopt half-chair, envelop and twisted sofa conformations respectively. The rings oxindole and cyclohexanone are parallel to each other but perpendicular to the pyrrolidine ring. C–H···N, C–H···O and N–H···O types of intra and intermolecular interactions control the molecules in the crystal packing.     

Structures of Two (<Emphasis Type="Italic">E</Emphasis>)-3-Substituted Cinnamoylbenzotriazole 1-Oxides

Abstract  

The molecule of (E)-3-(3-MeOC₆H₄CH=CHCO)-benzotriazole 1-oxide, 2, has a very near planar structure, while the 2-nitrophenyl ring is rotated out of the plane of the remaining atoms in (E)-3-(2-O₂NC₆H₄CH=CHCO)-benzotriazole 1-oxide, 1. The nitrogen oxide bond lengths in 1 and 2 are 1.258 (6) and 1.2683 (15) ?, respectively, and are in the region found for related compounds. There are no strong intermolecular hydrogen-bonds in either compound, instead there are weak C–H···O intermolecular hydrogen-bonds and π···π stacking interactions in 1, and C–H···O, C–H···π, and π···π stacking interactions in 2. Different three-dimensional arrays are generated in each case. Compound 1 crystallises in the orthorhombic space group Pna2₁, with a = 25.061 (2) ?, b = 3.6997 (2) ?, c = 14.2623 (12) ? and Z = 4. Compound 2 crystallises in the triclinic space group P-1, with a = 5.7297 (3) ?, b = 10.8440 (6) ?, c = 11.4965 (6) ?, α = 89.689 (3)°, β = 76.019 (3)°, γ = 75.047 (3)°, Z = 2.