Structure and conformation of a nickel complex: {2‐Hydroxo‐3‐piperidine‐1‐yl‐methyl‐N,N′(bis‐5‐bromobenzylpropylenediimine)nickel(II)perchlorate}

The title compound, a nickel complex [C₂₃H₂₆N₃O₂Br₂Ni.(ClO₄)] (CCDC 199520) crystallizes in triclinic space group P with the cell parameters a = 10.2560(4), b = 10.8231(4), c = 12.0888(5)Å, α = 99.404(1), β = 99.780(1), γ = 92.252(1)° and V = 1301.49(9)ų. The structure was solved by Patterson method and refined by full‐matrix least‐squares procedures to a final R = 0.0497 using 6287 observed reflections. In the complex, the piperidine ring takes chair conformation and the geometry around the Ni ion is slightly distorted square planar. The dihedral angle between the planes [N‐Ni‐N and O‐Ni‐O] is 9.4(1)°. The chelate ring containing both the nitrogen atoms adopts twisted boat conformation. The molecules in the crystal are stabilized by N‐H…O and C‐H…O types of hydrogen bonds in addition to a C‐H…π interaction. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)     

Monodentate coordination of N-[di(phenyl/ethyl)carbamothioyl]benzamide ligands: synthesis, crystal structure and catalytic oxidation property of Cu(I) complexes

New four-coordinated tetrahedral copper(I) complexes have been synthesized from the reactions between [CuCl(2)(PPh(3))(2)] and N-(diphenylcarbamothioyl)benzamide (HL1) or N-(diethylcarbamothioyl)benzamide (HL2) in benzene. These complexes have been characterized by elemental analyses, IR, UV/Vis, (1)H, (13)C and (31)P NMR spectroscopy. The molecular structure of both the complexes, [CuCl(HL1)(2)(PPh(3))] (1) and [CuCl(HL2)(PPh(3))(2)] (2) were determined by single-crystal X-ray diffraction, which reveals distorted tetrahedral geometry around each Cu(I) ion. The combination of 2 (0.005 mmol) with hydrogen peroxide (2.5 mmol) in acetonitrile is found to be an active catalyst for the oxidation of primary and secondary alcohols (0.5 mmol) to their corresponding acids and ketones, respectively, at room temperature.     

Crystal structures of N1, N5‐dibenzoyltetrahydro‐4‐methyl‐1, 5‐benzodiazepin‐2‐one (DBTBO) and tetrahydro‐4‐methyl‐1, 5‐benzodiazepin‐2‐one (TBO)

Adducing structural analogies between the two fused systems, N1, N5‐Dibenzoyltetrahydro‐4‐methyl‐1,5‐benzodiazepin‐2‐one, C₂₄H₂₀N₂O₃ (DBTBO CCDC 200341) and Tetrahydro‐4‐methyl‐1,5‐benzodiazepin‐2‐one, C₁₀H₁₂ N₂O (TBO CCDC 200342) helps to find the pharmacological differences from the view point of variant hetero atom substitutions in the hetero cycle. Both the diazepines crystallized in identical monoclinic space group P2₁/n with a = 14.1134(1) Å, b = 9.2444(1) Å, c = 16.3812(1) Å; β = 107.11(1)º, V = 2042.7(3) ų for DBTBO and a = 9.3363(7) Å, b = 10.4895(8) Å, c = 9.9852(7) Å, β = 91.314(1)º, V = 977.62(1) ų for TBO, respectively. The two structures were solved by direct methods and refined by full‐matrix least‐squares procedure to final R‐values of R1 = 0.0575(DBTBO) and R1 = 0.0984(TBO). Structural differences include non‐identical boat conformations of these seven‐membered rings and the different non‐bonding interactions in the benzodiazepine pair.     

Ultrasonic and DFT study of intermolecular association through hydrogen bonding in aqueous solutions of glycerol

The experimental measurements of density, viscosity and ultrasonic velocity of aqueous glycerol solutions were carried out as functions of concentration (0.1 ≤ m [mol kg^− 1] ≤ 1.0) and temperature (303.15 ≤ T [K] ≤323.15). The isentropic compressibility (β_s), acoustic impedance (Z), hydration number (H_n), intermolecular free length (L_f), classical sound absorption (α/f²)_class and shear relaxation time (τ) were calculated by using the measured data. These parameters have been interpreted in terms of solute–solvent interactions. The quantum chemical calculations were performed to study the hydrogen bonding in interacting complex formed between glycerol and water molecules. Computations have been done by using Density Functional Theory (DFT) method at B3LYP/6–31 + g(d) level of theory to study the equilibrium structure of glycerol, glycerol–water interacting complex and vibrational frequencies. The solution phase study was carried out using Onsager's reaction field model in water solvent. The computed vibrational frequencies are in good agreement with the main features of the experimental spectrum when four water molecules are considered explicitly with glycerol. The interaction energy (E_total), hydrogen bond lengths and dipole moment (µ_m) of the interacting complex are also presented and discussed with in the light of solute–solvent interactions.     

Crystal structures of 3-[1-Benzenesulfonyl-3-phenylsulfanyl-1H-indol-2-yl]-1-[4-(methyl (I)/methoxy (II) phenyl)]-2-phenyl-propane-1-one

The compounds 3-(1-Benzenesulfonyl-3-phenylsulfanyl-1H-indol-2-yl)-1-[4-methyl (I)/methoxy (II)phenyl)]-2-phenyl-propane-1-one crystallize in triclinic space group P . The details are: compound I a = 11.941(6) ?, b = 12.154(7) ?, c = 13.006(7) ?, α = 63.124(8)°, β = 84.464(9)°, γ = 64.810(8)°, V = 1519.7(14) ?³, Z = 2, D _cal = 1.284 Mg m⁻³, and R = 0.0382 (wR = 0.0978); compound II a = 11.897(6) ?, b = 12.268(6) ?, c = 13.001(7) ?, α = 61.919(8)°, β = 83.480(8)°, γ = 64.676(7)°, V = 1504.0(14) ?³, Z = 2, D _cal = 1.333 Mg m⁻³, and R = 0.0422 (wR = 0.1049). The indole ring system in both the molecules I and II are not strictly planar and the dihedral angles formed by the pyrrole and benzo planes are 4.0(7)° and 3.5(8)°, respectively. The C–HO, C–Hπ and ππ types of interactions stabilize the molecules in the unit cell in addition to van der Waal's forces in I and II.     

Growth,thermal and optical properties of cis-2,6-diphenyl-3-isopropylpiperidin-4-one – A new class of organic NLO material

A new class of organic nonlinear optical crystalline material, cis-2,6-diphenyl-3-isopropylpiperidine-4-one (3IPO), was prepared. The single crystals of the title material with good optical quality have been grown from its benzene solution by slow evaporation solution growth technique at ambient temperature. Vickers micro hardness measurement studies showed that the crystal belongs to a softer material category. The grown crystals were characterized through the spectroscopic techniques such as PXRD, UV–visible, FTIR and ¹H NMR spectra. The powder XRD reveals the structure of the crystal to be monoclinic system. The UV–visible spectrum was recorded to find the suitability of the title crystal for optical applications. FTIR & ¹H NMR spectra were recorded to confirm the presence of various functional groups and the molecular structure, respectively. The thermal stability of the crystal was established by TGA/DTA analysis. The second harmonic generation (SHG) in the crystal was confirmed using the modified Kurtz–Perry powder test employing Nd:YAG laser as the source of IR radiation and the SHG efficiency was found to be closer that of standard KDP.