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The catalytic effect of alkali metal carbonates, in situ generated carbene, and anionite in the transesterification reaction of alkyl benzoates with methanol, ethanol, benzyl alcohol, and cyclohexanol, as well as vegetable oils with methanol and ethanol was studied. Catalytic reactions with methanol occur at room temperature with yields close to quantitative. The reactions of the vegetable oils in the presence of potassium carbonate with small amounts of methanol or ethanol (3.2 eq) at room temperature lead to high yields of biodiesel fuel and are suitable for industrial use. [ABSTRACT FROM AUTHOR]

New carbene complex catalysts based on palladium chloride, including PEPPSI-complexes (PEPPSI = Pyridine-Enhanced Precatalyst Preparation Stabilization and Initiation), have been synthesized. These catalysts show high efficiency in Buchwald–Hartwig C–N cross-coupling between aryl chlorides/bromides and amines, including sterically shielded reagents, and high efficiency in the Suzuki–Miyaura C–C cross-coupling reaction, where their use results in the formation of several tetra-ortho-substituted biaryls at very low amounts of catalyst under mild conditions. Modification of the catalyst structure to the PEPPSI complex leads to an unexpected decrease in activity in the Buchwald–Hartwig amination, in contrast to the Suzuki–Miyaura reaction, in which the PEPPSI complex showed greater activity in some cases. [ABSTRACT FROM AUTHOR]

The efficiency of decontamination of blister and nerve agents was studied using the example of nucleophilic decomposition of paraoxone (O,O-diethyl-O-4-nitrophenyl phosphate) and oxidation of methylphenyl sulfide. Hydrogen peroxide solutions in an oil-in-water microemulsion containing synthetic nanoclay Laponite EP and polyvinylpyrrolidone polymer were studied as reactive decontamination systems. The base of the microemulsion consisted of an aqueous phase, a codetergent (isopropanol), oil (hexane), with a variation of detergent (cetylpyridinium chloride, sodium dodecyl sulfate, and Triton X-100). It was shown that the solubility of paraoxone and methylphenyl sulfide in the studied microemulsions increases by an average of 100 times or more compared to the solubility in water, and the substrate binding constants are 2-3 times higher than the binding constants in similar microemulsion media. It was found that the presence of nanoclay in the microemulsion provides a catalytic effect, i.e. an increase in the rate of decomposition of paraoxone and methylphenyl sulfide by at least 2 times. In addition, nanoclay thickens the microemulsion and, together with the polymer, increases the viscosity of the reaction medium. The determined kinetic parameters of decontamination and solubility of substrates allow us to conclude that the use of the investigated microemulsion system provides an acceleration of nucleophilic substitution and oxidation reactions by 150-350 times compared to the reaction rate in water. [ABSTRACT FROM AUTHOR]

New catalytic methods for the hydrodehalogenation of haloarenes with hydrogen and hydrogen-containing reagents (metal and non-metal hydrids, organic hydrogen-containing compounds, etc.), which are essential for fine organic synthesis and neutralization of toxic production waste and persistent organic pollutants. The paper focuses on such catalysts as complexes of stable heterocyclic carbenes, transition metals, and nanosized metal particles and their composites, as the most promising for industrial chemistry. Catalysts with particularly high efficiency have been highlighted. [ABSTRACT FROM AUTHOR]