Crystal structures and Hirshfeld surface analyses of bis(4,5-dihydrofuran-2-yl)dimethylsilane and (4,5-dihydrofuran-2-yl)(methyl)diphenylsilane

The title compounds, C10H16O2Si (1) and C17H18OSi (2), are classified as dihydrofurylsilanes, which show great potential as building blocks for various functionalized silanes. They both crystallize in the space group P\overline{1} in the triclinic crystal system. Analyses of the Hirshfeld surfaces show packing-determining interactions for both compounds, resulting in a polymeric chain along the [011] for silane 1 and a layered-interconnected structure along the b-axis direction for silane 2.

Synthesis and X-ray Crystal Structure of New Substituted 3-4’-Bipyrazole Derivatives. Hirshfeld Analysis, DFT and NBO Studies

A new compounds named 3-4’-bipyrazoles 2 and 3 were synthesized in high chemical yield from a reaction of pyran-2,4-diketone 1 with aryl hydrazines under thermal conditions in MeOH. Compound 2 was unambiguously confirmed by single-crystal X-ray analysis. It crystalizes in a triclinic crystal system and space group P-1. Its crystal structure was found to be in good agreement with the spectral characterizations. With the aid of Hirshfeld calculations, the H...H (54.8–55.3%) and H...C (28.3–29.2%) intermolecular contacts are the most dominant, while the O...H (5.8–6.5%), N...H (3.8–4.6%) and C...C (3.0–4.9%) are less dominant. The compound has a polar nature with a net dipole moment of 6.388 Debye. The BD(2)C31-C32→BD*(2)N4-C34 (27.10 kcal/mol), LP(1)N5→BD*(2)C31-C32 (36.90 kcal/mol), BD(1)C32-C34→BD*(1)C18-C31 (6.78 kcal/mol) and LP(1)N4→BD*(1)N5-C31 (7.25 kcal/mol) are the strongest π→π*, n→π*, σ-σ* and n→σ* intramolecular charge transfer processes, respectively.

The Crystal Structure of bis-(μ-N-ethyl-Nphenyldithiocarbamato- S,S’)-bis[(N-ethyl-Nphenyldithiocarbamato- κ2S,S’)zinc(II)]

The title material crystallises in the triclinic crystal system in space group P-1 with Z = 2. The unit cell dimensions are a = 8.7365(6)Å, b = 10.6009(7)Å, c = 12.0210(8)Å with α = 66.343(1)°, β = 79.566(1)°, γ = 83.150(1)° and V = 1001.6(1)Å3. The final R value is 0.0307 (3905 observed reflections: I >2σ(I)). The compound is best described as a species in which each metal atom is coordinated to two dithiocarbamato groups, one of which forms a secondary bridging interaction (through a S-atom) to a second [Zn(S2CNEtPh)2] unit. Thus, the title material is in the form of a dimeric aggregate. This complex is compared to related materials which contain N-atoms within the dithiocarbamato ligand that are derived from secondary amines containing two different organic functionalities.

The Crystal Structure of bis-(μ-N-ethyl-Nphenyldithiocarbamato- S,S’)-bis[(N-ethyl-Nphenyldithiocarbamato- κ2S,S’)zinc(II)]

The title material crystallises in the triclinic crystal system in space group P-1 with Z = 2. The unit cell dimensions are a = 8.7365(6)Å, b = 10.6009(7)Å, c = 12.0210(8)Å with α = 66.343(1)°, β = 79.566(1)°, γ = 83.150(1)° and V = 1001.6(1)Å3. The final R value is 0.0307 (3905 observed reflections: I >2σ(I)). The compound is best described as a species in which each metal atom is coordinated to two dithiocarbamato groups, one of which forms a secondary bridging interaction (through a S-atom) to a second [Zn(S2CNEtPh)2] unit. Thus, the title material is in the form of a dimeric aggregate. This complex is compared to related materials which contain N-atoms within the dithiocarbamato ligand that are derived from secondary amines containing two different organic functionalities.

Ab initio structure determination and morphology study of La1.26 Zr0.25 Na2.5 N0.24 O2.54 triclinic structure from powder x-ray diffraction data.

This paper deals with the ab initio structure determination of La1.26 N0.24 Na2.5 O2.54 Zr0.25 triclinic structure having triclinic crystal system via powder X-ray data using the Rietveld refinement method, and with physical properties characterization of a related solid solution at the room temperature structure of three compounds belonging to the Aurivillius family La1.26 N0.24 Na2.5 O2.54 Zr0.25 has been analyzed. La1.26 N0.24 Na2.5 O2.54 Zr0.25 crystallizes in a triclinic crystal system with P-1 space group. The starting material was Na2CO3,Zr(NO3)4 La2O3 for the Zr,La and Na analogues was derived from ab initio methods and refined using the Rietveld refinement method using JANA software package and visualization by Diamond computer program. The cations Na and La are disordered over the Zr sites while the La cation is found exclusively in the layers. The cell parameters are a=4.1040 Å b=9.9102 Å c=17.6117 Å α=98.4299° β=93.4378° γ=92.2041°.The morphology and electrical properties are carried out of cited oxide.

Crystal structure of 4-(dimethylamino)pyridin-1-ium-2,5-dichloro-3,6-dioxocyclohexa-1,4-diene-1,4-bis(olate) 4-dimethylaminopyridine (2:1) water undeca-solvate

The structure of the title compound, 4-(dimethylamino)pyridin-1-ium-2,5-dichloro-3,6-dioxocyclohexa-1,4-diene-1,4-bis(olate) 4-dimethylaminopyridine water undeca-solvate, C57H87Cl5N12O21, obtained from interaction between chloranilic acid (caH2), and dimethyl aminopyridine (DMAP) has been determined by single crystal X-ray diffraction. The title compound, (DMAPH)5(ca)2.5·(DMAP)·11H2O, crystallized in the triclinic crystal system with space group, P (no. 2), a = 13.3824(15) Å, b = 13.4515(17) Å, c = 19.048(2) Å, α = 86.014(4)°, β = 88.821(4)°, γ = 86.367(4)°, V = 3413.3(7) Å3, Z = 2, T = 100(2) K, μ(MoKα) = 0.294 mm-1, Dcalc = 1.414 g/cm3, 59413 reflections measured (3.76° ≤ 2Θ ≤ 56°), 16405 unique (Rint = 0.0517, Rsigma = 0.0589) which were used in all calculations. The final R1 was 0.0460 (I ≥ 2σ(I)) and wR2 was 0.1271 (all data). Using supramolecular chemistry principles, proton donors (chloranilic acid) and acceptor (DMAP) were combined to generate a multicomponent hydrogen-bonded system. Due to the presence of protonated bases (DMAPH+), the dominant interactions are the N+-H···O hydrogen bonds, whereas the negative charges of an acceptor from the chloranilate dianion (ca2-) are delocalized. Additionally, three sets of water clusters in the title compound were identified, namely a cyclic pentamer, a linear, and an acute-shaped trimer water cluster. It was further observed that strong hydrogen bond interactions occurred between the solvated aqua molecule(s) acting as a proton donor and the neutral DMAP acting as a proton acceptor. The crystal packing is further stabilized by O-H···Cl and C-H···Cl weak halogen interactions. The lattice metric strength is further held by observed π-π stacking interactions (centroid-centroid) with inter centroid distances between sets of the DMAPH rings of 3.624(3), 3.642(4), 3.739(3), 3.863(3) and 3.898(3) Å, respectively.

Structural Elucidation of Enantiopure and Racemic 2-Bromo-3-Methylbutyric Acid

Halogenated carboxylic acids have been important compounds in chemical synthesis and indispensable research tools in biochemical studies for decades. Nevertheless, the number of structurally characterized simple α-brominated monocarboxylic acids is still limited. We herein report the crystallization and structural elucidation of (R)- and rac-2-bromo-3-methylbutyric acid (2-bromo-3-methylbutanoic acid, 1) to shed light on intermolecular interactions, in particular hydrogen bonding motifs, packing modes and preferred conformations in the solid-state. The crystal structures of (R)- and rac-1 are revealed by X-ray crystallography. Both compounds crystallize in the triclinic crystal system with Z = 2; (R)-1 exhibits two crystallographically distinct molecules. In the crystal, (R)-1 forms homochiral O–H···O hydrogen-bonded carboxylic acid dimers with approximate non-crystallographic C2 symmetry. In contrast, rac-1 features centrosymmetric heterochiral dimers with the same carboxy syn···syn homosynthon. The crystal packing of centrosymmetric rac-1 is denser than that of its enantiopure counterpart (R)-1. The molecules in both crystal structures adopt a virtually identical staggered conformation, despite different crystal environments, which indicates a preferred molecular structure of 1. Intermolecular interactions apart from classical O–H···O hydrogen bonds do not appear to have a crucial bearing on the solid-state structures of (R)- and rac-1.

Synthesis, crystal structure and antioxidant evaluation of N-(4-formylpiperazine-1-carbonothioyl)benzamide

New benzoylthiourea derivative, N-(4-formylpiperazine-1-carbonothioyl)benzamide was prepared by the reaction of benzoylisothiocyanate with 1-piperazinecarboxaldehyde in acetone as solvent. The compound was characterized by FT-IR and multinuclear 1H and 13C NMR spectroscopy techniques. The benzoylthiourea molecule was obtained in crystalline form by recrystallization in DMSO. Single crystal X-ray diffraction study indicates that compound crystallized in triclinic crystal system and crystal data for C13H15N3O2S, space group P-1 (no. 2), a = 7.3016(9) Å, b = 7.7380(9) Å, c = 12.9815(16) Å, α = 103.581(4)°, β = 102.153(4)°, γ = 102.409(4)°, V = 669.46(14) Å3, Z = 2, T = 296(2) K, μ(MoKα) = 0.243 mm-1, Dcalc = 1.376 g/cm3, 31184 reflections measured (6.72° ≤ 2Θ ≤ 53.46°), 2822 unique (Rint = 0.0582) which were used in all calculations. The final R1 was 0.0501 (>2σ(I)) and wR2 was 0.1493 (all data). Intramolecular N-H···O hydrogen bond is stabilized the trans geometry of the thiono and the carbonyl groups. The heterocyclic piperazine ring makes a dihedral angle of 48.50(15)° with the benzene ring. Antioxidant test by DPPH method showed that compound exhibits good antioxidant activity of about 75%.

New Copper(II) Complexes of Pyridine-2-carboxaldehyde-N-(2-pyridyl)hydrazone and 2-Hydroxy-1-naphthaldehyde-semicarbazone: Synthesis, Characterization, DNA Binding and Antimicrobial Activity Studies

Two new copper(II) complexes of pyridine-2-carboxaldehyde-N-(2-pyridyl)hydrazone [Cu(PCPH)(H2O)2](NO3)(H2O)2 (1) and 2-hydroxy-1-naphthaldehyde-semicarbazone [Cu(II)(HNSC)H2O]·NO3·H2O (2) have been synthesized and characterized by spectroscopic techniques and single crystal X-ray diffraction study. Complex 1 crystallized as square pyramidal coordination complex in triclinic crystal system while complex 2 crystallized as square planar complex in monoclinic crystal system. EPR spectral patterns are of normal order of energy levels, i.e. x2-y2 >> z2 > xy > xz, yz, with partial covalent character. Both copper(II) complexes were found to be groove binding to calf-thymus DNA and showed activity against E. coli, S. aureus, B. cereus and E. faccium.

Complex of Tris(Phenanthroline)Cobalt(II)Trifluoroacetate: Characterisation and Powder XRD Analysis

The powder complex of tris(phenanthroline)cobalt(II) trifluoroacetate (TFA) has been prepared by interaction of cobalt(II) nitrate, phenanthroline (phen) in aqueous solution with drops of ethanol, and an excess of saturated aqueous solution of sodium trifluoroacetate, whereupon the yellowish powder was produced. AAS measurment for the metal content, equivalent conductance (1:2), and TGA-DTA of the powder suggest the corresponding formula of [Co(phen)3](TFA)2.5H2O. The efffective magnetic moment of 4.9 BM indicates the high-spin nature of this complex which corresponds to three unpaired electrons in the electronic configuration of Co(II) with significantly higher than the spin only value due to the orbital contribution. UV-Vis spectrum of the complex reveals the d-d spin-allowed transition bands as well as the MLCT and intraligand band. The estimating transition energy ratio of 2.04 for ν2/ν1, is clearly in the range for octahedral configuration. The infrared spectral property indicates the main mode of vibrations for the functional groups of ligand phen and TFA, and thus supports strongly the formula proposed for this complex. The corresponding powder XRD was then refined using Rietica-Le Bail method and found to be fit as triclinic crystal system with space group of PĪ.