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Chloromethylation of cross-linked styrene-divinylbenzene beads with subsequent quaternization with amines was carried out. The resulting anion exchangers were tested as catalysts for the addition of CO2 to oxiranes and as sorbents for the separation of Zr, Nb, Hf, Ta, and Th salts from nitric acid solutions. The anion exchanger can be used in six catalytic cycles for the reaction of CO2 addition to oxiranes, which led to cyclic carbonates in quantitative yields. [ABSTRACT FROM AUTHOR]

The effect of structure of alkylammonium halides on the outcome of cycloaddition of carbon dioxide to oxiranes was studied. The conversion of epichlorohydrin to chloromethylethylene carbonate depends nonlinearly on the length of the hydrocarbon chain in the alkylammonium halide catalyst. Tetraethylammonium and benzyltriethylammonium were the most effective cations in the catalyst used. Acetone was the solvent of choice for this reaction under the studied conditions. [ABSTRACT FROM AUTHOR]

Ammonium derivatives of triethanolamine have been effectively used as catalysts for the addition of CO2 to epoxides. The iodine additive was found to exert a positive effect on the catalytic activity of these polyhydroxy-containing salts. [ABSTRACT FROM AUTHOR]

A group of available catalysts based on polyethylenimine quaternized with p-xylylene dichloride followed by subsequent exchange of anions was developed. The influence of the nature of halide ions and electronic and steric factors of the substituents in epoxides on the reaction rate of carbon dioxide addition to epoxides was studied. The catalytic capabilities of the adduct of polyethylenimine with iodine were considered. [ABSTRACT FROM AUTHOR]

Sodium and potassium halides in combination with molecular iodine are efficient catalysts for the solvent-free addition of CO2 (10–56 atm) to epoxides giving organic carbonates. [ABSTRACT FROM AUTHOR]

The addition of the oxirane derivatives to CO2 was found to occur without Lewis acid involvement but requires the presence of the Lewis base. The reaction was carried out at atmospheric pressure by CO2 bubbling through the starting ether in the presence of a source of halide anion or trichloroacetate anion, which provides the formation of ethylenecarbonate derivatives in preparative amounts. The reactivity of halide anions in the addition of the studied oxirane derivatives to CO2 decreases in the order I− > Br− > Cl− > F− >> Cl3CCOO−. The quantum chemical calculations of the reaction of CO2 with epichlorohydrin show that the reaction consists of consecutive processes of nucleophilic addition and nucleophilic ipso-substitution, which explains the catalytic effect of the Lewis bases and the order of their activity. [ABSTRACT FROM AUTHOR]

An easy-to-prepare recyclable catalyst of quaternary ammonium nature and based on commercially available and inexpensive macroporous polymeric sorbent Purolite A103 resin has been devised for the carbon dioxide addition to epoxides. The catalyst can be easily separated due to its 0.6–0.85 mm bead size and recycled at least seven times. The catalyst makes it possible to carry out the reaction under solvent-free conditions. It is insensitive to the steric and electronic effects of various epoxy substrates. [ABSTRACT FROM AUTHOR]

Onium salt, N1, N1, N1, N5, N5, N5-hexaethylpentane-1,5-diammonium dibromide, was used as a catalyst for the addition of CO2 to epoxides. An influence of insoluble supports on the rate of the process as well as possibility of recycling of the catalytic system are described. In addition, the effects of temperature and CO2 pressure on the yields of products are discussed. [ABSTRACT FROM AUTHOR]

A complex study of sodium and potassium halides as catalysts of the addition of CO2 to epoxides to yield organic carbonates was carried out. The activity of these metal iodides was investigated. The conditions allowing achievement of a quantitative conversion of epoxides into carbonates were found by varying the temperature, carbon dioxide pressure, and available co-solvents. [ABSTRACT FROM AUTHOR]

Silica gel with the additives of tetraalkylammonium halides serves as an efficient catalyst for the solvent-free insertion of carbon dioxide into epoxides (10–56 atm of CO2, 105–100 °C), leading to cyclic carbonates with quantitative conversion. [ABSTRACT FROM AUTHOR]

Silica gel with the additives of tetraalkylammonium halides serves as an efficient catalyst for the solvent-free insertion of carbon dioxide into epoxides (10–56 atm of CO2, 105–100 °C), leading to cyclic carbonates with quantitative conversion. [ABSTRACT FROM AUTHOR]