Palladium(II) and platinum(II) tetrakisthiourea dichloride bis(7-hydroxy-5-methyl[1,2,4]triazolo[1,5a]pyrimidine) dihydrate solvates

The title compounds palladium(II) and platinum(II) tetrakisthiourea dichloride bis(7-hydroxy-5-methyl[1,2,4]triazolo[1,5a]pyrimidine (Hmtpo)) dihydrate solvates, have been synthesized by reacting thecis-[MCl₂(Hmtpo)₂] (where M=Pt(II), Pd(II)) complexes with an excess of thiourea (tu) and the structure of the palladium compound was solved by X-ray diffraction. Crystals of [Pd(tu)₄]Cl₂·2Hmtpo·2H₂O are triclinic with space groupP and unit cell dimensionsa=7.972(1),b=9.049(1),c=11.808(2)Å, =88.20(1), =75.15(1), =76.54(1)^o. The cation [Pd(tu)₄]²⁺ is centrosymmetric involving four sulfur thiourea atoms in a near square planar environment. The triazolopyrimidine molecules, chloride anions and water molecules do not take part in the metal center coordination but interact by hydrogen bonding between them and the thiourea moieties. A comparison between powder diffraction data of palladium(II) and platinum(II) compounds clearly indicates that both compounds are isomorphous.     

Two Different Compounds Formed from Copper(II) tetrafluoridoborate and [1,2,4]triazolo[1,5-a]pyrimidine. Synthesis,Spectroscopy and Single-Crystal Structures

Abstract  

Two coordination compounds copper(II) with tetrafluoridoborate as the anion and [1,2,4]triazolo[1,5-a]pyrimidine (abbreviated as tp) as the ligand are presented, together with their crystal structure and spectroscopic properties. A light blue compound [Cu(tp)₄(H₂O)₂](BF₄)₂(CH₃OH) (1) with a tetragonal chromophore and a dark blue compound [Cu(tp)₅](BF₄)₂(CH₃OH) (2) are formed from the same batch. Compound (2) has a quite unusual geometry for Cu(II) with just 5 tp ligands, homoleptically coordinated to the metal ion. Both compounds show interesting hydrogen-bond interactions in the solid state, where coordinated water is intramolecularly bound to non-coordinated N atoms of tp (in 1), and methanol is attached to the anion (in 2).     

Synthesis,bioactivities, and X-ray structure analysis of 2-cyano-5-methylpyrazolo[1,5-a]pyrimidine

The title compound crystallizes in the monoclinic space group P2₁/c with unit cell parameters a = 3.8380(12), b = 11.994(4), and c = 16.245(5) Å, β = 90.743(5)^∘, V = 747.7(4) ų, and Z = 4. The final reliability index is 0.0409 for 1088 observed reflections. All the non-hydrogen atoms in the title compound are almost coplanar, the largest deviation from the mean plane being 0.030(2) Å for atom C5. The crystal cohesion is accentuated by C–H⋅sN hydrogen bond. The X-ray crystallography analysis indicates that the methyl group is at the 5-position of the compound 4 rather than at the 7-position of the isomer 4-1. The preliminary biological test shows that the title compound has moderate herbicidal activity.     

Crystal and molecular structure of diaquabis(thiocyanato-N)bis(5-methyl-[1,2,4]triazolo[1,5-a]pyridine-N3)cobalt(II), [Co(NCS)2(C6H6N4)2(H2O)2]

The X-ray crystal structure of the title compound, [Co(NCS)₂(C₆H₆N₄)₂(H₂O)₂], has been determined. The crystals are monoclinic, space groupC2/c, with cell dimensionsa=15.6901(5),b=7.9248(10),c=16.1278(12) Å,=94.4(8)°V _c=1999.44 ų,M _r=479.18,Z=4,D _x=1.5918 Mg m³,Cu K radiation (graphite crystal monochromator, =1.54051 Å), (CuK)=39.08 cm^–1,F(000)=980.00 andT=290 K. Final conventionalR-factor=0.051, andR _w=0.053 for 1430 observed reflections and 141 variables. The structure was solved using the programsPatsys andDirdif. The Co atom is octahedrally coordinated (CoN₂O₂N₂ chromophore), with only the 5-methyl-[1,2,4]-triazolo[1,5-a]pyrimidine (5mtp) ligands in thetrans positions. The triazolo pyrimidine rings are planar and coordinated through their N(3) atoms. The H₂O ligands are also H-bond donors to N(4) (intramolecularly) and to the S atoms of the NSC anions (intermolecularly).     

Red and Blue Compounds Formed from Copper(II) Bromide and the Ligand 7-Isobutyl-5-methyl-[1,2,4]triazolo[1,5-a]pyrimidine: Synthesis, Spectroscopy and Single-Crystal Structures

Abstract  

Two newly synthesized coordination compounds copper(II) bromide with the ligand 7-isobutyl-5-methyl[1,2,4]triazolo[1,5-a]pyrimidine (abbreviated as ibmtp) are presented, together with their 3D crystal structure and spectroscopic and magnetic properties. The compounds are CuBr₂(ibmtp)₂ (1) (red crystals) and [CuBr(ibmtp)₄]Br(H₂O)₃ (2) (blue crystals). In (1) the Cu(ii) ion is present in a distorted tetrahedral environment, while in (2) the Cu(ii) ion has a square pyramidal geometry. These crystal structures are also the first ones reported with the ligand ibmtp.     

Spectroscopic studies, antimicrobial activities, and crystal structure of N-[2-hydroxy-1-naphthylidene]3, 5-bis(trifluoromethyl)aniline

A new Schiff base compound has been synthesized by the reaction of 2-hydroxy-1-naphthaldehyde with 3,5-bis(trifluoromethyl)aniline.The title compound was characterized by elemental analysis, IR,¹H NMR,¹³C NMR, and UV–Visible techniques.Its UV–Vis spectra was examined in polar and nonpolar solvents and in acidic and basic media. The crystal structure of the compound showed the OH group to be ortho to the imine group. It crystallizes in the monoclinic space group P2₁ with a = 11.328(2), b = 6.125(1), c = 11.937(2) ?, V = 825.1(2) ?³, D _x = 1.543 g cm⁻³and Z = 2. An intramolecular O1- H⋯N1 [2.558(7) ?] hydrogen bond stabilizes the molecule. The compound has also been characterized by its antimicrobial activities. The ligand has been screened in vitro against the organisms Escherichia coli ATCC 11230, Staphylococcus aureus ATCC 6538, Klebsiella pneumoniae UC57, Micrococcus luteus La 2971, Proteus vulgaris ATCC 8427, Pseudomonas aeruginosa ATCC 27853, Mycobacterium smegmatis CCM 2067, Bacillus cereus ATCC 7064, and Listeria monocytogenes ATCC 15313, the yeast cultures Candida albicans ATCC 10231, Kluyveromyces fragilis NRRL 2415, Rhodotorula rubra DSM 70403, Debaryomyces hansenii DSM 70238, and Hanseniaspora guilliermondii DSM 3432.     

Crystal and molecular structure of Dibromobis ([1,2,4]triazolo[1,5-a]pyrimidine-N3)zinc hemihydrate,C10H8N8Br2Zn·1/2 H2O

The structure of the title compound (C₁₀H₈N₈Br₂Zn·1/2H₂O), prepared from the ligand and zinc bromide in ethanol, was solved by X-rays analysis.M _r =465.18, monoclinic, space groupP2₁/n,a=21.2376(11),b=7.1339(6),c=20.0469(11) Å,=98.583(4)°,V _c =3003.2 ų,Z=8,D _x =2.057 Mg m^–3,(Cu K)=87 cm^–1,F(000)=1832,T=300 K. Final conventionalR-factor=0.034 andR _w =0.036 for 4255 unique reflections withI> 3(I) out of 5685 measurements. The structure was solved using automatic programsPatsys andDirdif. The two independent molecules are almost identical. The Zn atom is tetrahedrally coordinated by two Br atoms and two N(3) atoms of the triazolopyrimidine ligands. The planar triazolopyrimidine ligands make angles of 94.0 and 57.5° (moleculeA) with the ZnBr₂ plane (98.6 and 57.0° for moleculeB). The water molecule is involved in hydrogen bonds with bromine only.On leave from Chemistry Department, University of Benin, Benin-City, Nigeria.     

Crystal structures of 3-(4-pyridinyl)-5,6,7,8-tetrahydro-1,2,4-triazolo[4,3-a]pyrimidine and its 6-hydroxy derivative

(1): C₁₀H₁₁N₅,M _r=201.23, from water, P ,a=6.913(1),b=8.198(2),c=9.212(2) Å, =72.36(2), =109.03(2) and =88.13(1)^o,D _x=1.436 g/cm³,Z=2. FinalR=0.043 for 1477 observed reflections. (2): C₁₀H₁₁N₅O,M _r=217.23, from methanol/water solution. P2₁/c,a=9.291(2),b=11.263(3),c=10.454(3) Å, and =114.05(1)^o,D _x=1.444, g/cm³,Z=4. FinalR 0.056 for 1587 observed reflections. The data were collected on a diffractometer at room temperature. Structures were solved by direct methods and refined by anisotropic full-matrix least-squares method. In the solid state both molecules have the same conformation and are packed in similar manner. The planarity of the condensed triazole ring and its electrons conjugation with a lone pair at N8 impose C6 sofa conformation of the saturated diazine rings. Hydroxy group in2 is in an energetically unfavorable axial position. Both in1 and2, N8–H ... N34 hydrogen bonds join molecules into infinite chains, and O6–H ... N1 hydrogen bonds in2 span the chains into two-dimensional net. The molecules in hydrogen bonded chains and sheets have the same chirality.     

Synthesis,spectral, X-ray diffraction and DFT studies on 1-(2-methyl-2-propenyl)-3-(2,3,4,5,6-pentamethylbenzyl)benzimidazolium chloride hydrate

A new benzimidazole based N-heterocyclic carbene (NHC) salt (1) was synthesized by the reaction of benzimidazole precursor with alkyl halide. The structure of 1 was determined by elemental analysis, FT-IR, ¹H NMR and ¹³C NMR spectroscopy tecniques and X-ray crystallography. The compound crystallized in the triclinic space group P-1 with two molecules in the unit cell. The optimization of 1 was firstly performed at B3LYP/6-311G++(d,p) level, then the theoretical spectral studies performed and compared with the experimental values. Besides the frontier molecular orbital energies and chemical reactivity analysis of 1, together with the electrostatic potential and molecular electrostatic potential analyses were performed at the same level of theory.     

Cobaloxime derivatives: synthesis and spectroscopic studies of alpha-furilglyoximate of cobalt (III), X-ray structure of bis(thiourea)bis(alpha-furilglyoximato)cobalt(III) nitrate

-Furilglyoxime (H₂afdo) complexes of cobalt(III) were used to synthesize H₂afdo-cobaloximes with thiourea, triphenylphosphine, and aniline astrans-axial ligands. Encapsulation of the H-bonded species with BF₃OEt₂ resulted in stable BF₂-capped macrocycles which mimic the central metal core of the biological molecules such as vitamin B₁₂ etc. Solution chemistry and spectroscopic measurements of the BF₂-macrocycles as well as H-bonded cobaloximes revealed six-coordinated cobalt(III) as the central atom and a short hydrogen bond in the case of latter. X-Ray structure of a representative complex [Co(Hafdo)₂(thiourea)₂]NO₃ (Haldo=-furilglyoxime anion) confirmed a pseudo-octahedral geometry around cobait(III) with thiourea bonded to axial positions. The oxygen atoms of furyl groups are not involved in any kind of bonding and the overall structure of the complex differs from that of the H₂dmg-cobaloximes (H₂dmg=dimethylglyoxime).     

New sulfur derivatives of 2,3-dichloropyrrolo[1,2-a] benzimidazol-1-one. Demonstration of regioselective thiolate addition and X-ray diffraction structures of 2-chloro-3-methylthiopyrrolo[1,2-a]benzimidazol-1-one and 2,3-di(benzylthio)pyrrolo[1,2-a]benzimidazol-1-one

The reaction of thiols with the heterocyclic compound 2,3-dichloropyrrolo[1,2-a] benzimidazol-1-one (1) has been investigated as a route to new redox-active, bidentate sulfur ligands. Treatment of 1 with either methylthiol or benzylthiol in the presence of pyridine affords monosulfide compounds 2-chloro-3-methylthiopyrrolo[1,2-a] benzimidazol-1-one (2) and 2-chloro-3-benzylthiopyrrolo[1,2-a]benzimidazol-1-one (3) and the disulfide derivatives 2,3-di(methylthio)pyrrolo[1,2-a]benzimidazol-1-one (4) and 2,3-di(benzylthio)pyrrolo[1,2-a]benzimidazol-1-one (5). The substitution of the first chlorine group in 2,3-dichloropyrrolo[1,2-a]benzimidazol-1-one (1) occurs regioselectively at C-3 to produce 2-chloro-3-methylthiopyrrolo[1,2-a]benzimidazol-1-one (2) and 2-chloro-3-benzylthiopyrrolo[1,2-a]benzimidazol-1-one (3), followed by replacement of the remaining chlorine group to furnish the disulfide compounds 4 and 5. The new thiols have been isolated by column chromatography and characterized in solution by spectroscopic methods. The molecular structures of 2-chloro-3-methylthiopyrrolo[1,2-a]benzimidazol-1-one and 2,3-di(benzylthio)pyrrolo[1,2-a]benzimidazol-1-one have been determined by X-ray crystallography. Compound 2 crystallizes as two independent molecules in the monoclinic space group P2₁/c, a = 13.221(2) Å, b = 18.478(2) Å, c = 8.948(1) Å, = 100.088(3)°, V = 2152.3(5) ų, Z = 8, and d_calc = 1.547 Mg/m³; R = 0.0354, R_w = 0.0739 for 2820 reflections with I > 2(I). Compound 5 crystallizes in the triclinic space group P-1, a = 5.180(1) Å, b = 11.494(2) Å, c = 17.243(3) Å, = 86.024(3)°, = 88.606(4)°, = 81.235(3)°, V = 1012.1(4) ų, Z = 2, and d_calc = 1.360 Mg/m³; R = 0.0354, R_w = 0.0692 for 2655 reflections with I > 2(I). The redox properties of the disulfide compounds 4 and 5 have been explored by cyclic voltammetry, where a one-electron reduction at ca. –1.10 V has been observed for each compound. The site of electron accession in has been established by carrying out molecular orbital calculations at the extended Hüuckel level on the model compound 2,3-di(thio)pyrrolo[1,2-a]benzimidazol-1-one.     

Structure, thermal behavior, and IR investigation of bis(3-amino-1,2,4-triazolium)monohydrogen monophosphate

Chemical preparation, calorimetric studies, crystal structure, and IR spectrometric investigation of (C₂H₅N₄)₂HPO₄, denoted ATZP, are described. The compound crystallizes in the monoclinic system with C2/c space group. Its unit cell dimensions are a = 13.589(2) Å b = 11.105(2) Å c = 15.734(3) Å = 104.68(2)°, V = 2296.8(7) ų, and Z = 8. The structure of the title compound consists of a three dimensional network of H-bonds connecting all its components. The IR spectrum of ATZP is reported and discussed on the basis of group theoretical analysis.     

Synthesis,structural and thermal studies of tetrathioureacopper(I) chloride crystals

Tetrathioureacopper(I) chloride, hereafter abbreviated as TCC, was synthesised and single crystals were obtained from saturated aqueous solution by slow evaporation (solution growth) method at room temperature. The crystals obtained are bright, colourless and transparent having well defined external faces. The grown crystals were characterized through elemental analysis, single crystal X‐ray diffraction study, thermal analysis, electron spin resonance spectroscopy and Fourier Transform infrared spectroscopy. The elemental analysis confirms the stoichiometry of the compound. The single crystal diffraction studies indicate that TCC crystallises in the tetragonal lattice and the unit cell parameters are a = b = 13.4082 Å, c = 13.8074 Å, V = 2482.29 ų, α = β = γ = 90°. Space group and the number of molecules per unit cell (Z) are found to be P4₁2₁2 and 8 respectively. The TG curve of the sample shows a prolonged decomposition from 210 to 628.3 °C, from which the decomposition pattern has been formulated. The endothermic peaks in the DTA curve indicate melting and decomposition of the compound at 165.2 and 633.8 °C respectively. An exothermic peak in high temperature DSC indicates a phase transition in the compound at 274.8 °C. Thermal anomalies observed in the low temperature DSC at –163.3, –152.0, –141.5, –108.3, 1.0 and 12.1 °C in the heating run and –157.1 and –153.9 °C in the cooling run reveal first order phase transitions in the crystal. The peaks observed at –146.2 °C in both the heating and cooling runs suggest occurrence of a second order phase transition in this compound. The IR spectroscopic data were used to assign the characteristic vibrational frequencies of various groups present in the compound. The ESR study confirms that the copper is in the +1 oxidation state in the complex. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)     

Synthesis,Crystal Growth,Structural and Physical Properties of bis(thallium) bis(nitrilotriacetato) zirconate dihydrate,Tl2Zr(N[CH2COO]3)2 · 2H2O

Single crystals of Tl₂Zr(N[CH₂COO]₃)₂ · 2H₂O having optical quality and dimensions up to 30 × 25 × 12 mm have been grown from aqueous solutions by controlled lowering of temperature. The raw material was synthesized as the first fraction of crystallization during evaporation of an aqueous solution of (CH₃NH₃)₂Zr(N[CH₂COO]₃)₂ · 2H₂O and TlNH₂SO₃. A crystal structure analysis revealed an isotypy to the K₂Zr(N[CH₂COO]₃)₂ · 2H₂O family, space group Ccc2, a₁ = 14.780(2)Å, a₂ = 14.933(2)Å, a₃ = 8.901(1)Å, Z = 4, ρ_calc. = 3.145 gcm^‐3. Thermal stability, thermal expansion and pyroelectric, dielectric, piezoelectric, elastic and thermoelastic properties have been determined. All properties are closely related to those of Rb₂Zr(N[CH₂COO]₃)₂ · 2H₂O.     

Synthesis,Crystal Structure and Biological Activity of 7-(4-Methylpiperazin-1-Yl)-5-[4-(Trifluoromethyl)Phenyl]pyrazolo[1,5-a]Pyrimidine-3-Carbonitrile

Crystallography Reports - The title compound C19H17F3N6 was synthesized and structurally characterized by infrared and mass spectroscopy, 1H NMR, elemental analyses and single crystal X-ray...     

Crystallographic and Computational Analysis of the Supramolecular Structure of 2,5-Dimethylpyrazolo[1,5-a]pyrimidin-7(4H)-one

Abstract  

The structure of 5-dimethylpyrazolo[1,5-a]pyrimidin-7(4H)-one 1 has been determined by X-ray crystallography. The compound 1 crystallizes in the space group P−1 with two molecules in the asymmetric unit solvated with one molecule of the acetic acid The unit cell parameters are a = 8.796(1) ?, b = 10.531(1) ?, c = 10.680(1) ?, α = 96.901(2)o, β = 98.135(2)o, γ = 107.248(2)o. In the crystal molecules A and B are linked into R ₂²(9) hydrogen bonded rings and these rings form chains parallel to [101] Overall, the supramolecular structure 1 consists of two hydrogen bonded and two π–π stacking dimers. An energetic interplay between these dimers has been studied using B3LYP DFT calculations. In addition π–π interactions are analyzed using the Bader’s atoms in molecules’ (AIM) theory.     

Crystal structure analyses of bis(triphenyl- phosphoranyliden)ammonium bis(pentafluoroethyl) argentate, [Ph3P=N=PPh3][Ag(C2F5)2] and bis[bis(triphenylphosphoranyliden)ammonium] tetrachloro-diargentate, [Ph3P=N=PPh3]2[ClAg(μ-Cl)2AgCl]

Bis(triphenylphosphoranyliden)ammonium bis(pentafluoroethyl)argentate, [Ph₃P=N= PPh₃][Ag(C₂F₅)₂] (1) and bis[bis(triphenylphosphoranyliden)ammonium]tetrachloro-diargentate, [Ph₃P=N=PPh₃]₂[ClAg(μ-Cl)₂AgCl] (2) were crystallized from the reaction mixture of pentafluoroethylsilver(I) and bis(triphenylphosphoranyliden)ammonium chlo-ride. Crystallization of 1 occurs in the centrosymmetric monoclinic space group P2₁/c (No. 14) with a = 17.083(2) Å, b = 11.600(2) Å, c = 19.833(2) Å, β = 109.66(1)°, V = 3700.8(7) ų, Z = 4. 2 crystallizes in the centrosymmetric orthorhombic space group Pbca (No. 61) with a = 19.540(1) Å, b = 15.926(1) Å, c = 20.160(1) Å, V = 6273.6(3) ų, Z = 8.     

The preparation, characterization and X-ray structural analysis of tetrakis[1-methyl-3-(2-propyl)-2(3H)-imidazolethione]zinc(II) tetrafluoroborate and tetrakis[1-methyl-3-(1-butyl)-2(3H)- imidazolethione]zinc(II) tetrafluoroborate

Two compounds, [Zn(mipit)₄][BF₄]₂ (1) and [Zn(mnbit)₄][BF₄]₂ (2) have been synthesized and characterized via standard solid and solution state methods including single crystal X-ray crystallography (mipit: 1-methyl-3-(2-propyl)-2(3H)-imidazolethione and mnbit: 1-methyl-3-(1-butyl)-2(3H)-imidazolethione). Compound 1 crystallizes in monoclinic space group P2₁/n with a = 11.804(2) ?, b = 16.710(3) ?, c = 25.763(5) ?, γ = 90.14(3)° and Z = 4, whereas compound 2 crystallizes in tetragonal space group $${\rm I}\bar{4}$$ with a = b = 11.6517(16) ?, c= 16.820(3) ?, and Z = 2. Both complexes are high melting, colorless water soluble 2:1 electrolyte solids that state have flattened tetrahedral ZnS₄ coordination geometry. The isopropyl analog is slightly more distorted than the n-butyl analog, and the degree of distortion is not directly related to the steric bulk of the ligand.