Solid-state structure of copper complexes of N-(2-carboxyethyl)chitosan

The sorptivity for ions of the Irving-Williams series (Zn2+, Cu2+, Co2+, Ni2+) was estimated for the chelate sorbent N-(2-carboxyethyl)chitosan cross-linked by nanosecond electron-beam irradiation. The maximum capacity reaches 3.7 mmol/g using a mixture of the appropriate sulfates at pH 4.5. The selectivity of copper sorption is 80%. The structure of the coordination sphere of the copper complexes with N-(2-carboxyethyl)chitosan was investigated by ESR spectroscopy

Novel methods for synthesis and sorption properties of N,O-(2,3-dihydroxy) propylchitosan

The direct addition of glycidol to chitosan in a gel medium under exposure to ultrasound afforded the chelating aminopolymer N,O-(2,3-dihydroxy) propylchitosan with a degree of substitution up to 2.3. The sorption characteristics of the crosslinked aminopolymers with respect to boron-containing ions were estimated. © 2013 Pleiades Publishing, Ltd

Synthesis of poly[N-(2,3-dihydroxypropyl)aminostyrene], a new sorbent for boron(III) ions

A procedure was developed for preparation of poly[N-(2,3-dihydroxypropyl) aminostyrene] via successive stages of nitration, reduction, and glycidol treatment of polystyrene, which gives the polymer with a maximal degree of functionalization. The composition and structure of the intermediates and end products of the polymer-analogous reactions were characterized by elemental analysis, IR spectroscopy, and solid-state 13C NMR spectroscopy. The sorption characteristics of poly[N-(2,3-dihydroxypropyl)aminostyrene] toward boroncontaining ions were assessed. © 2013 Pleiades Publishing, Ltd.This study was financially supported by the Ural Division, Russian Academy of Sciences (project no. 12-S-3-1003) and by the Council of the President of the Russian Federation for Young Scientists and Leading Scientific Schools Supporting Grants (project no. МК-5745.2013.3)

The investigation of esters of polychlobiphenylcarboxylic acids by gas chromatigraphy/mass-spectrometry

Методом газовой хроматографии/масс-спектрометрии проведено исследование полихлорбифенилкарбоновых кислот (ПХБК), полученных путем карбонилирования смеси полихлорированных бифенилов (ПХБ) марки «Совол», и их метиловых, этиловых и 2,2,2-трифторэтиловых эфиров. Исследовано газохроматографическое поведение сложных эфиров ПХБК и выявлены пути фрагментации их молекулярных ионов в условиях электронной ионизации. Показано, что фрагментация происходит путем последовательного отрыва сложноэфирных групп, а затем атомов хлора. Установлено, что при карбонилировании ПХБ образуются ПХБК, содержащие от одной до пяти карбоксильных групп.The polychlorobiphenylcarboxylic acids (PCBA) were obtained by carbonylation of polychlorinated biphenyls (PCB) (technical mixture Sovol). A gas chromatography behavior and mass spectra of methyl, ethyl and 2,2,2-trifluoroethyl esters of these acids were studied. It was found that a fragmentation (electron ionization) of molecular ions is, firstly, a sequence of esters groups loss and then of chlorine atoms. It was showed that the PCBA contained from 1 to 5 carboxylic groups

Silyl Glyoxylates. Conception and Realization of Flexible Conjunctive Reagents for Multicomponent Coupling

This Perspective describes the discovery and development of silyl glyoxylates, a new family of conjunctive reagents for use in multicomponent coupling reactions. The selection of the nucleophilic and electrophilic components determines whether the silyl glyoxylate reagent will function as a synthetic equivalent to the dipolar glycolic acid synthon, the glyoxylate anion synthon, or the α-keto ester homoenolate synthon. The ability to select for any of these reaction modes has translated to excellent structural diversity in the derived three- and four-component coupling adducts. Preliminary findings on the development of catalytic reactions using these reagents are detailed, as are the design and discovery of new reactions directed toward particular functional group arrays embedded within bioactive natural products