Over the past years, polymer-supported reagents have been extensively studied and used in various applications. One class of such reagents is called "scavengers," which can be used to easily eliminate compounds in a solution. The present work describes the production of a resin that can be used for scavenging ketones and aldehydes using low-cost reagents and simple reaction steps, named here Amb15-Iso. This resin is obtained by reacting a low-cost commercial sulfonyl resin, Amberlyst-15, with isoniazid, a drug used for the treatment of tuberculosis. Acetone and isobutyraldehyde were used as carbonyl compound models. The reactions were monitored in-line by ATR-FTIR and results showed that the polarity of the solvent influences the kinetics of the production of the resin and water proved to be the fastest solvent. For the scavenging of acetone and isobutyraldehyde, two factors showed to have an impact in the amount of compounds captured: the polarity of the solvent and the solubility of water in the solvent. The capacity of scavenging acetone in water varied from 0.11 to 0.28 mmol per gram of resin, depending on the initial acetone concentration. The equilibrium of this reaction was modeled and the equilibrium constant was calculated to be 0.63 6 0.07 L mol 21 . The resin was also recycled and tested in a second round of scavenging and results showed that there was not much difference between the new resin and the recycled one, proving that the Amberlyst-15 could be reused for a second cycle of scavenging. V C 2015 Wiley Periodicals, Inc. J.Appl. Polym. Sci. 2015, 132, 42291.

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Dimethyl fumarate (DMF) has recently gained attention due to its use as a pro-drug in different pharmaceutical preparations, here in we present our work on a cascade methodology in short reaction times and quantitative yields.

A low-cost isoniazid-based scavenger resin was previously prepared and successfully used to capture aldehydes and ketones in solution by using a batch approach. The present work compares batch and continuous processes in relation to the preparation of the scavenger resin and the effectiveness of cyclohexanone scavenging. The batch preparation of the resin proved to be the better choice because the resin produced in the continuous flow suffered deformation on its surface that prevented access to the active sites in the internal porous polymer matrix. Conversely, the continuous-flow approach presented higher capturing yields than the batch. The optimized scavenging process was successfully used to remove formaldehyde present in a solution and the carbonyl compounds present in an ethanolic extract of Cymbopogon citratus.

A catalyst free decarboxylative trichloromethylation of imines to afford different trichloromethyl sulfonyl and sulfinyl amines has been presented.

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Summary Nitrogen-generating systems (NGSs) are mainly used in the oil industry to fluidize low melting point organic deposits and gas hydrate buildups. They are exothermic reactions between two nitrogenous salts in acidic catalytic media. This work investigates the use of CO2 to promote NGS reactions instead of commonly used acids such as acetic and citric acids, which can be problematic for corrosion control. Sodium nitrite and ammonium chloride were the reactants, and CO2 performance was evaluated for up to 4 hours at 5 and 25°C, and either under autogenous pressure at 10, 25, and 50 bar of CO2 or pressurized at 10 bar of CO2 by adding 40 bar of nitrogen (totaling 50 bar). The nitrite conversion was determined by measuring the concentration of residual nitrite using titration. Thus, it was verified that the CO2 effectively promoted the NGS at various experimental conditions. The nitrite conversion increased with increasing CO2 pressure and increasing temperature. Moreover, the nitrite conversion was enhanced in the pressurized system (PS) because the high pressure enabled the dissolution of CO2 in the aqueous medium, and therefore, the constant formation of carbonic acid, favoring the acidic catalytic medium at the reaction. This advantage was confirmed by carrying out an NGS catalyzed by acetic acid, in which the pH increases as reagents are consumed, and therefore, a lower nitrite conversion is achieved. The use of CO2 also converts the NGS in a process more suitable for flow assurance applications in offshore oil production, particularly in the Brazilian presalt fields where the coproduced CO2 can be used.