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A facile and efficient one-pot procedure for the preparation of functionalized dihydro-lH-indol-4(5H)-ones by a catalyst-free, three-component reaction of 1,3-dicarbonyl compounds, arylglyoxal monohydrate and enaminones under mild conditions in excellent yield is reported. This synthesis was confirmed to follow the group-assisted-purification (GAP) 0 chemistry process, which can avoid traditional purifications, chromatography, and recrystallization. [ABSTRACT FROM AUTHOR]

Batch isotherm experiments were carried out to select the best chromatographic supports for the purification of beet distillery condensates with the aim of recovering fermentable water. Adsorption parameters of four inhibitory solutes of the condensates chosen as targets were obtained, leading to the selection of a weak anion-exchanger and a polystyrenic resin. These results were further used for the chromatographic scaleup. Dynamic adsorption experiments run on both resins with a synthetic mixture of the four target solutes showed the presence of competition for the adsorption. The extended Langmuir model was then found to be applicable for a first estimation of the solute breakthrough. The treatment efficiencies of the two supports were confirmed with an industrial condensate, indicating components in the effluent that were not considered did not significantly affect the adsorption of the main compounds. Eventually, a combination of the two complementary resins was proposed for complete effluent detoxification. [ABSTRACT FROM AUTHOR]

Synthetic oligodeoxynucleotides are purified with use of a catching by polymerization, washing, and releasing approach. The method does not require any chromatography, and purification is achieved by simple operations such as shaking, washing, and extraction. It is therefore useful for large-scale purification of synthetic oligonucleotide drugs. In addition to purification of oligonucleotides, this catching by polymerization concept is expected to be equally useful for purification of other synthetic oligomers such as peptides and oligosaccharides. [ABSTRACT FROM AUTHOR]

A fluorous analogue of TBAF has been developed for its use in the clean removal of silicon-derived protecting groups. Purification of the crude mixtures by fluorous solid-phase extractions allowed alcohols, amines, and carboxylic acids to be obtained in high purity, with no need of chromatographic separations. The moderate reactivity of fluorous TBAF was exploited in selective deprotections of several bifunctional molecules. [ABSTRACT FROM AUTHOR]

A one-pot, high-yielding iodination of hydroxypyridines and hydroxyquinolines is described. The iodination proceeds under mild conditions, and the products are obtained in high yield without the need for chromatographic purification. In addition, the iodination works on both 2- and 4-hydroxypyridines and -hydroxyquinolines. [ABSTRACT FROM AUTHOR]

The article presents a study which examines the reactivity of 10-I-3 hypervalent iodine trifluoromethylation reagent with phenols to know if its derivatives are beneficial to pharmaceutical industry. The purification process of the regeants by sublimation or column chromatography is discussed. It also explores other substituted phenols experiments to determine if such reactivity are extended through oxidation and triflouromethylation.

A practical protocol for the preparation of a parallel solution-phase library of oxazabicycle is reported. Target compounds were obtained in moderate to good yields by a Yb(OTf) 3-catalyzed one-pot tandem reaction from various anisidines, aromatic aldehydes, isobutyraldehyde, and 4-hydroxycoumarins/dimedone. Purification of the final products by either recrystallization in ethyl acetate/methylene chloride or column chromatography allowed easy isolation of the 18 components of the array. [ABSTRACT FROM AUTHOR]

A procedure is described for precise Hg isotope ratio measurements by solution nebulization multicollector inductively coupled plasma mass spectrometry (MC- ICPMS). Hg was released from geological samples using aqua regia extraction and then separated from other matrix elements with the aid of anion-exchange chromatography using strongly basic Dowex 1-X8 anion-exchange resin. Performance of the chromatographic procedure was evaluated using various types of replacement anions for elution of mercury, including L-cysteine, thiourea, NO3-, and SO42-. A solution of 0.15% L-cysteine in 0.06 M HCl was found to be the most convenient eluent for subsequent MC-ICPMS measurements. The optimized procedure provides separation of Hg from virtually all concomitant matrix elements while maintaining quantitative (>95%) recovery. In addition, band displacement chromatographic experiments were conducted to assess whether the anion-exchange purification can produce Hg isotope fractionation artifacts. No isotope fractionation between the Hg(II)-L-cysteine complex in aqueous solution and Hg ions in the anion-exchange resin was observed. Hg isotope ratio measurements were performed using the bracketing standards approach and on-line correction for instrumental mass discrimination using TI spiking and normalization to the 205Tl/203Tl ratio. The absence of spectral interference during Hg isotope ratio measurements was verified using a three-isotope plot. Uncertainties of Hg isotope ratio measurements for replication of the entire procedure, expressed as two standard deviations, are better than ±0.08‰/amu. The described procedure facilitates study of variations in the isotopic composition of Hg in nature. [ABSTRACT FROM AUTHOR]

The article cites a study focusing on the use of a nonoxidative, nonchromatographic method for the removal of the contaminant D5h isomer. The researchers in this study used a reactive diamio silica with the stir and field approach (SAFA) and compared the reactivity of this isomer relative to the Sc3N@C80 isomer and empty cage fullerness. It was concluded that the SAFA process with diamino silica rapidly removes the D5h contaminant.