Search results for "Aniline"

Optical properties of biocompatible polyaniline nano-composites

2006

Abstract Polyaniline (PANI) is an electro-active polymer of great interest thanks to its outstanding physical and chemical properties which make it suitable for various applications in optics, bioelectronics, biosensors, diagnostics and therapeutic devices. Unfortunately, PANI is infusible and insoluble in most common solvents and, thus, very difficult to process. In the attempt of improving processability, yet preserving its interesting properties, PANI has been synthesized in the form of particles and dispersed into a hydrogel matrix. The synthesis of PANI–hydrogel composites proceeds via γ-irradiation of PANI dispersions as obtained by ‘in situ’ polymerization of aniline in the presence …

Inside Cover: Reagent- and Metal-Free Anodic C−C Cross-Coupling of Aniline Derivatives (Angew. Chem. Int. Ed. 17/2017)

2017

Kinetic experiments on the binding of metyrapone to liver microsomes

1969

Kinetic experiments on the inhibition of oxidative microsomal O- and N-demethylations by metyrapone (2-methyl-1, 2-bis(3-pyridyl)-l-propanone, Su 4885) were carried out using mouse liver microsomes as the enzyme source. The model substrates were p-nitroanisole and N-monomethyl-p-nitroaniline. It was shown that the inhibition is competitive. The K i for metyrapone is 0.42 × 10−4 M and for the reduced metabolite of metyrapone 1.15×10−4 M. Their spectral dissooiation constants as determined from difference spectra have almost the same values. From this it is concluded that the degree of inhibition is correlated to the amount of metyrapone bound to cytochrome P-450. Metyrapone does not seem to …

Genotoxicity of the fungicide dichlofluanid in seven assays

1991

Seven different endpoints for detection of genotoxicity have been used to demonstrate the DNA-altering properties of Dichlofluanid, a fungicide commonly used in viticulture pest control. Each endpoint (DNA synthesis inhibition test, alkaline viscosimetry, umu-test, alkaline filter elution, FADU-test, 32P-postlabeling, and electron microscopy) shows clear evidence of genotoxicity. These data indicate that application of the fungicide dichlofluanid may be mutagenic and/or carcinogenic for exposed humans.

Palladium-catalyzed formation of secondary and tertiary amines from aryl dihalides with air-stable ferrocenyl tri- and diphosphines: Synthesis and X-…

2014

Abstract Robust, air-stable tridentate and bidentate ferrocenylphosphines 1,2-bis(diphenylphosphino)-1′-(diisopropylphosphino)-4-tert-butylferrocene, L5, and 1,1′-bis(diisopropylphosphino)-3,3′-bis(tert-butyl)ferrocene, L9, combined with 1 mol% of [PdCl(η3-C3H5)]2 led to two new catalytic systems which allow the coupling of aniline derivatives with mono- and dihaloarenes to form functionalized diarylamines and triarylamines. The excellent selectivity of the reactions avoids the deleterious dehalogenation of the substrates and products. The X-ray structure characterization of the related complex [PdCl2(L9)] is reported in which ligand L9 in its meso form is significantly distorted.

Palladium C–N bond formation catalysed by air-stable robust polydentate ferrocenylphosphines: a comparative study for the efficient and selective cou…

2014

The arylation of aniline derivatives with dichloroarenes under a low palladium content (below the currently used 5 to 10 mol%) was studied using nine different ferrocenylphosphine ligands, including the easily accessible 1,1′-bis(diphenylphosphino)ferrocene, DPPF. The electron-enriched air-stable tridentate ferrocenylpolyphosphine 1,2-bis(diphenylphosphino)-1′-(diisopropylphosphino)-4-tert-butylferrocene, L5, employed in 2 mol% in combination with 1 mol% [PdCl(η3-C3H5)]2 allows an efficient and selective coupling, while such demanding substrates currently induce chloroarene homocoupling and/or dehalogenation processes. The scope and limitation of the optimized system are explored, with a fo…

Advantages of monolithic over particulate columns for multiresidue analysis of organic pollutants by in-tube solid-phase microextraction coupled to c…

2011

Abstract The performance of a monolithic C 18 column (150 mm × 0.2 mm i.d.) for multiresidue organic pollutants analysis by in-tube solid-phase microextraction (IT-SPME)-capillary liquid chromatography has been studied, and the results have been compared with those obtained using a particulate C 18 column (150 mm × 0.5 mm i.d., 5 μm). Chromatographic separation has been carried out under isocratic elution conditions, and for detection and identification of the analytes a UV-diode array detector has been employed. Several compounds of different chemical structure and hydrophobicity have been used as model compounds: simazine, atrazine and terbutylazine (triazines), chlorfenvinphos and chlorp…

Determination of aniline in vegetable oils by diazotization and coupling in a microemulsion medium

1990

Abstract A microemulsion containing sodium dodecyl sulphate and n -pentanol in a mass ratio of 1 : 4, water and a vegetable oil was investigated using pseudo-tenary phase diagrams. The medium can co-solve important amounts of vegetable oils and aqueous solutions over a wide range of ionic strengths. A procedure for the determination of 1.4–140 μg ml −1 of aniline in vegetable oils using ionic diazotization and coupling reactions was developed. The absorbance was measured in an optically clear microemulsion containing 4% or 20% of oil. The procedure is much simpler and rapid than the official chromatographic methods and gives almost the same limits of detection (ca. 05 μg ml −1 ) using no mo…

Determination of amitraz and its transformation products in pears by ethyl acetate extraction and liquid chromatography-tandem mass spectrometry.

2008

A method has been developed for identification and quantification of the acaricide amitraz and its transformation products, 2,4-dimethylaniline (DMA), 2,4-dimethylformamidine (DMF) and N-2,4-dimethylphenyl-N-methylformamidine (DMPF) in pears. The analytes were extracted using ethyl acetate and anhydrous sodium sulphate. Analysis was performed by liquid chromatography-electrospray tandem mass spectrometry (LC-ESI-MS/MS) in the positive ion mode using a triple quadrupole (QqQ) instrument. Two precursor-product ion transitions were monitored for each compound in the selected reaction monitoring (SRM) mode. The method was validated with pears taken from the orchard before the amitraz treatment …

Theoretical Multipolar Atom Model Transfer in Nitro-Derivatives of N-Methylaniline

2014

The nitroanilines are an example of compounds in which the coexistence of electron-rich and electron-deficient substituents, connected through a conjugated π-electronic system, makes their molecular second-order hyperpolarizability and second-harmonic generation efficiency particularly high. This property makes them extremely interesting from the point of view of charge density distribution analysis. The electron density of three isomeric molecules, i.e., N-methyl-2-nitroaniline, N-methyl-3-nitroaniline, and N-methyl-4-nitroaniline, was calculated theoretically through the multipolar atom model transfer. Two types of refinement models, i.e., multipolar atom model (MAM) and independent atom …