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N-[2-(1-hydrazonoethyl)-3-benzofuranyl]-p-toluenesulfonamide
No full textThe structure of the title compound, C17H17N3O3S, has been determined. It consists of two planar moieties, the benzofuran and S-aryl systems, which form an angle of 65.6(1)degrees with one another
STRUCTURE OF 2-ACETYL-3-AMINOBENZOFURAN
Full text linkThe title compd. is monoclinic, space group P21/c, with a 5.191(2), b 16.586(4), c 10.214(3) Å, and β 104.00(3)°; dc = 1.364 for Z = 4. The final R = 0.056 for 1391 reflections. At. coordinates are given. In the mol. the aminobenzofuran moiety is planar. The N-C and C:O bond lengths are comparable with the dimensions usually found for the amide group. The carbonyl group must be assigned a syn configuration with respect to the N atom. Two N...O H bonds are present
Structure and NMR-spectra of N-(2-(Alpha-hydrazonobenzyl)-3-benzofuranyl)-p-toluenesulfonamide
No full textC22H19N3O3S, M(r) = 405.48, monoclinic, P2(1)/c, a = 8.296 (3), b = 26.859 (8), c = 8.820 (4) angstrom, beta = 99.53 (1)-degrees, V = 1938.3 angstrom-3, Z = 4, D(x) = 1.389 g cm-3, lambda(Mo K-alpha) = 0.71073 angstrom, mu = 1.87 cm-1, F(000) = 848, T = 293 K, R = 0.056 for 2074 reflections with I greater-than-or-equal-to 3-sigma(I). The alpha-hydrazonobenzyl group has a syn configuration with respect to N(1). Two hydrogen bonds, involving N and O atoms, are present. In solution, the H-1 mononuclear NMR spectrum and two-dimensional homonuclear correlated spectroscopy experiments (COSY) confirm the presence of hydrogen bonding
Crystal structure of the gold(I) complex [Au(tfp)Cl] with tfp =(C4H3O)(3)P
No full textThe Au(I) complex [Au(tfp)Cl] with tfp = (C4H3O)3P has been prepared and characterised.
It crystallises in the monoclinic P21/n space group with z = 4, a = 9.837(3),
b = 12.684(4), c = 11.103(5)A° , β = 91.58(2)◦ and V = 1384.8(2)°A3. The structure of the
complex consists of molecules connected in head-to-tail dimers by a metal-halogen contact
as generally found in analogus complexes of lighter coinage metals. The typical feature of
halogen gold compounds, the Au Au interaction, seems prevented by the bulk of the tfp
ligand
A 1,5-DIARYLPYRROLE DERIVATIVE
No full textThe structure of the 1,5-diarylpyrrole derivative, ethyl 5-(4-chlorophenyl)-1-(2,4-dichlorophenyl)-2-methyl-3-pyrrolecarboxylate, C20H16Cl3NO2, has been determined. The orientation assumed by the phenyl rings corresponds to the deepest of the two minima obtained from ab initio calculations. All bond distances and angles are in the expected ranges
Electrospray mass spectrometry characterization of ionic silver(I) and gold(I) complexes of the ligand L = 1-benzyl-2-imidazolyl-diphenylphosphine. Counterion influence in the ionization processes and crystal structure determination of [Ag2L3][CF3SO3]2.
No full textOne of the most discussed and studied aspects of the silver(I) coordination complexes chemistry is the influence of the counterions in the solid state structures and in the ligand exchange reactions occurring in solution; this kind of chemistry is pretty rare in the gold(I) coordination derivatives. Some silver(I) and gold(I) complexes of the type L2M2X2 (where L is 1-benzyl-2-imidazolyl diphenylphosphine I, M = Ag, X = BF4 II; X=NO3 III, X=CF3SO3 IV, X = BAr4 V), L3M2X2 (M = Ag, X =NO3 VI, X=BF4 VII, X = BAr4 VIII, X =CF3SO3 IX), LAuCl (X), L2Au2X2 (X = BF4, XI) and L2AuBF4 (XII) have been synthesized. In the paper is reported the unprecedented structure of IX. From the analysis of the structures, it can be argued that in the silver(I) complexes the counterions deeply affect the structure by strongly interacting with the metal centres. In addition it is also reported the study of these complexes by the ESI mass spectrometry with the target of both studying the counterion effect in the ionization process, and to characterize the above described complexes by this new soft mass spectrometry technique
A single-strand helical motif induced by self-assembly of [Ag(TFP)]+ moieties with nitrate anions - 31P NMR spectroscopic and X-ray crystal structure characterization of the complexes involved in equilibrium reactions of silver salts and TFP ligand
No full textCapillary electrochromatography on methacrylate based monolithic columns: Evaluation of column performance and separation of polyphenols
No full textFused-silica capillary columns (100 lm I.D.) englobing a porous monolithic stationary phase were prepared by in situ copolymerization of 2-ethylhexyl methacrylate, ethylene glycol dimethacrylate and 2-acrylamido-2-methylpropanesulfonic acid (AMPS) in the presence of a porogenic mixture containing 1-propanol, 1,4 butanediol and water. The influence of the monomers ratio and the porogen solvent composition as well as the content of AMPS in the polymerization mixture on column total porosity and efficiency was investigated to attain minimum HETP values for the reversed-phase capillary electrochromatography separation of bioflavonoids. For the most promising column, the van Deemter plots, in both l-HPLC and CEC, were also evaluated. In CEC the reduced plate height was found almost constant (1.6–2.0) within the range of linear mobile phase velocity between 0.2–2.0 mm s)1. The chemical and mechanical stabilities of the monolithic column over a wide range of buffer pH (2-10) and time were satisfactory. Furthermore, the effects of mobile phase parameters, such as buffer concentration and organic modifier content, on the electroosmotic flow were studied systematically. CEC separations of standard mixtures of polyphenols, including flavonols, flavanones and flavanones-7-O-glycosides, were accomplished in less than 8 min. The CEC separation of the major flavanone glycoside constituents in the extract from a freshly squeezed grapefruit juice was also reported
STRUCTURE OF N-(2-ACETYL-3-BENZOFURANYL)-P-TOLUENESULFONAMIDE
Full text linkThe title compd. is monoclinic, space group P21/n, with a 11.574(5), b 8.375(4), c 17.342(8) Å, and β 108.0(3)°; Z = 4 for dc = 1.369. The final R = 0.045 for 2777 reflections. The structure consists of 2 planar moieties, the benzofuran system and the S-aryl one, which form an angle of ∼79°. There is evidence for a H bond between the N atom of the -NH-SO2 group and the O atom of the Ac group, causing the CO group to be syn with resp. to the N atom. At. coordinates are given
Mono and Tetranuclear Gold(I) Complexes of Tris(1-benzylimidazole-2-yl)-phosphine.
No full textThe reaction of tris(1-benzylimidazole-2-yl)phosphine, (Bzim)3P, 1, with Ph3AsAuCl in 1:1 stoichiometric ratio produced (Bzim)3PAuCl, 2. The reaction of (Bzim)3PAuCl with NaAuCl4 in 1:1 stoichiometry in dichloromethane gives an orange-yellow crystalline tetranuclear gold(I) cluster [{μ-N,N’-(Bzim)3PAuCl}2Au2][AuCl2][AuCl4], 3. Complex [{μ-N,N’-(Bzim)3PAuCl}2Au2][AuCl2]2, 4, is formed when the reaction stoichiometry of (Bzim)3PAuCl and NaAuCl4 is 2:1. The crystal structure of 3 shows the formation of a 12-membered macrocycle with Au•••Au distances of ∼3.0 A°. The structures of (Bzim)3PAuCl and 3 show Au•••H-C interactions ranging from 2.57 to 2.95A°.
The interest in tetranuclear gold clusters is due to their potential application as precursors for CO and olefin oxidation, their structural features and the presence of short Au•••Au interactions possibly influencing the optoelectronic properties observed in various polynuclear Au(I) compounds
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