<Emphasis Type="Italic">N</Emphasis>-Alkylation of benzimidazoles with ketonic Mannich bases and the reduction of the resulting 1-(3-oxopropyl)benzimidazoles

Benzimidazole, benzimidazoles diversely substituted at position 2, and 5,6-dimethylbenzimidazole have been alkylated at N ¹ with ketonic Mannich bases derived from acetophenones, acetylnaphthalenes, 2-acetylthiophene and 1-tetralone to afford a series of novel 1-(3-oxopropyl)benzimidazoles. The reduction of these transamination products with NaBH₄ in methanol produced the corresponding 1-(3-hydroxypropyl)benzimidazoles in excellent yields.      

Chiral enantiopure bis(thio)ureas derived from TADDOL and their carboxylate complexation capacity

New chiral enantiopure ureas and thioureas with (R,R)-TADDOL backbone were synthesized. Bis-(thio)ureas with C2 symmetry were obtained from TADDOL iso(thio)cyanates and bifunctional amino-(thio)ureas from TADDAMINE, respectively. These were tested for carboxylate recognition capacity and the association constant was determined for the most stable complex.      

Diironcarbonyl-coumarin complex: preparation, intramolecular electron transfer, and electro-generation of hydrogen

A new organometallic complex coupling photoactive coumarin to a diironhexacarbonyl unit has been successfully prepared and its composition and electronic structure confirmed by elemental and spectroscopic analyses. Emission spectral analysis of the complex reveals photoinduced intramolecular electron transfer from coumarin to the iron-carbonyl moiety. The compound is electrochemically reduced at −1.24 V vs. Fc/Fc⁺. This reduction is irreversible, attesting to the instability of the complex. Electrochemical evolution of hydrogen in the presence of the complex has been studied and results are discussed.      

Removal of uranyl ions from UO2(NO3)2 solution by means of Chlorella vulgaris and Dunaliella salina algae

This paper deals with a study of the biosorption of UO₂ ²⁺ ions on two green algae: Chlorella vulgaris and Dunaliella salina. By investigating the retention degree versus contact time from Langmuir and Freundlich biosorption isotherms, kinetic investigations and FTIR spectra it was found that the biosorption process was greater for Chlorella vulgaris than for Dunaliella salina. A new kinetics method is proposed to establish the reaction order concerning the biosorption process of uranyl ions on these biomasses.      

Recent progress for capillary electrophoresis with electrochemical detection

Capillary electrophoresis (CE) is an attractive technique in separation science because of its high separation performance, short analysis time and low cost. Electrochemical detection (EC) is a powerful tool for CE because of its high sensitivity. In this review, developments of CE-EC from 2008 to August, 2011 are reviewed. We choose papers of innovative and novel results to demonstrate the newest and most important progress in CE-EC.      

Ionic liquid mediated recyclable sulphonimide based organocatalysis for aldol reaction

Sulphonimide based organocatalyst was used to catalyze the aldol reaction in ionic liquid media. On the basis of yield and selectivity the ionic liquid mediated system was found superior in comparison with organic solvents. The added advantages of this ionic liquid mediated organocatalysis are easy recovery of product and the recyclability of the organocatalyst.      

Ionic liquid promoted Diels-Alder Reaction between anthrone and maleimides

Ionic liquids (IL) are gaining importance as green solvents. Imidazolium ionic liquid [bmim]⁺[Cl]⁻, an environmentally benign solvent, was found to promote the Diels-Alder reaction between anthrone and maleimides at room temperature with excellent yields. The ionic liquid played a dual role as solvent and catalyst.      

Synthesis of fluorescent carboxylic acid ligands for construction of monolayers on nanostructures

Two new long-chain carboxylic acids (1, 2) bearing strong fluorescent group pyrene as ligands for Self-Assembled Monolayers (SAMs) have been synthesized. The multistep targeted synthesis is accomplished by use of Pyren-1-yl methylamine hydrochloride and employing simplified synthetic protocols. Compound 2 contains a chiral center purposely introduced along the atom chain in order to make it suitable for chiro-optical studies of the resulting SAMs.      

Asymmetric transfer hydrogenation of prochiral ketones catalyzed by aminosulfonamide-ruthenium complexes in ionic liquid

Chiral aminosulfonamides containing imidazolium group were used as ligands for the ruthenium(II)-catalyzed asymmetric transfer hydrogenation of prochiral ketones in ionic liquid, affording good to excellent conversions and enantiomeric excesses. The catalytic system could be easily recovered and reused several times.      

Removal of cadmium and copper ions by <Emphasis Type="Italic">Trichosporon cutaneum</Emphasis> R57 cells immobilized onto polyvinyl alcohol/tetraethoxysilane hybrid matrices

Polyvinyl alcohol (PVA) and tetraethoxysilane (TEOS) hybrid materials were prepared by sol-gel methods and tested as matrices for immobilization of Trichosporon cutaneum R57, capable of removing cadmium and copper ions from aqueous solutions. A kinetic model was applied and the effects of matrix TEOS content on the copper and cadmium uptake equilibria and rate constants were investigated.      

Metathesis transformations of unsaturated derivatives of β-diketones

Selected β-diketones bearing unsaturated derivatives have been demonstrated to undergo homo-metathesis and cross-metathesis with selected olefins in the presence of Grubbs catalysts. The reactions led to respective homo- and cross-metathesis products mainly with good yields and selectivities.      

One-pot, three-component condensation of 2-hydroxybenzaldehyde derivatives, primary amines with alkyl isocyanides to N-alkyl-2-(2-hydroxyphenyl)-2-imino-acetamides

One-pot, three-component condensation of 2-hydroxybenzaldehyde derivatives, primary amines with alkyl isocyanides is reported. N-alkyl-2-(2-hydroxyphenyl)-2-iminoacetamide derivatives are generated presumably via the preliminary formation of N, N′-disubstituted benzo[b]furan-2,3-diamines and subsequent oxidation with molecular oxygen.      

Amino acid and vitamin determinations by TLC/HPTLC: review of the current state

Several methods to determine amino acids and vitamins in biological and pharmaceutical samples have been reported. Thin layer chromatography (TLC) finds its place when the relatively costly equipment required by other methods is unavailable. This review covers the 1991–2010 literature on TLC/HPTLC (high performance thin layer chromatography) amino acid and vitamin determinations. It gives an overview of the special features as well as the problems in TLC/HPTLC determinations of amino acids and vitamins. Various chromatographic systems useful in amino acid and vitamin identification, separation and quantitation of are presented in tabular form. Future prospects of TLC/HPTLC for amino acid and vitamin determinations are also discussed.      

A direct method for the decontamination of a fly ash amended wet soil,artificially polluted with dioxins

We report hereby the first method of direct treatment of a wet soil containing toxic polychloroderivatives. Using a system with metallic Ca and 5% Rh fixed on charcoal in methanol, soil samples artificially polluted with fly ash containing polychloro-dibenzodioxins (PCDDs), polychloro-dibenzofurans (PCDFs) and coplanar polychlorinated biphenyls (co-PCBs), and having 69.2% to 84.6% moisture content, were successfully treated and decontaminated. This treatment afforded excellent hydrodechlorination yields for the 29 most toxic congeners of PCDDs, PCDFs and PCBs (98.3% degradation yield based on toxic equivalent quotient — or TEQ) after a 24 h treatment, at room temperature.      

Hydrophilic interaction chromatography in drug analysis

Hydrophilic interaction chromatography (HILIC) is an increasingly popular alternative to conventional HPLC for drug analysis. It offers increased selectivity and sensitivity, and improved efficiency when quantifying drugs and related compounds in complex matrices such as biological and environmental samples, pharmaceutical formulations, food, and animal feed. In this review we summarize HILIC methods recently developed for drug analysis (2006–2011). In addition, a list of important applications is provided, including experimental conditions and a brief summary of results. The references provide a comprehensive overview of current HILIC applications in drug analysis.      

Efficient and solvent-free synthesis of 1-amidoalkyl-2-naphthols using <Emphasis Type="Italic">N,N,N’,N’</Emphasis>-tetrabromobenzene-1,3-disulfonamide

N,N,N,’N’-Tetrabromobenzene-1,3-disulfonamide [TBBDA] is found to be a reusable catalyst for efficient synthesis of various amidoalkyl naphthols from β-naphthol, aromatic aldehydes and urea in good to high yields under solvent-free conditions.      

Pressure induced structural phase transitions—A review

The contemporary status of experimental as well as theoretical advances within the special view of structural phase transitions is reviewed. A brief outline of phase transitions and its classification is presented first. High-pressure experimental techniques developed for studying the structural phase transitions and elastic properties are reviewed. The complete set of theoretical and experimental data obtained is for the group II–IV alkaline earth chalcogenides. Here the authors review the currently used calculations and high-pressure behavior of these materials and the theoretical work that has been done on them.      

Use of multivariate statistical techniques to optimize the separation of isoflavones by liquid chromatography

The aim of this paper is to optimize and validate a high performance liquid chromatography (HPLC) method for separation and quantification of five isoflavones. A statistical central composite design was used to separate all peaks. These multivariate procedures were efficient in determining the optimal separation condition using resolution, capacity factor, asymmetry and number of theoretical plates.