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The lattice strain effect in Pd–Ni core–shell nanocubes on the selectivity of urea electrolysis is elucidated, which can facilitate catalyst design for efficient urea waste treatment and concomitant cathodic hydrogen production or CO2 reduction.

Ni(OH)2-catalyzed electrochemical oxidation of ammonia can be used for the synthesis S- or P-containing NH4NO3-based fertilizers with up to 72% faradaic efficiency and up to 98% ammonia removal efficiency.

The precise control of nanostructure and surface atomic arrangement can be used to tune the electrocatalytic properties of materials and improve their performance. Unfortunately, the long-term structural stability of electrocatalysts with complex nanoscale morphology, a necessary requirement for industrial implementation, often remains elusive. Here we study how electrochemical and complex current behaviours affect the nanoscale object and its structural stability during electrocatalysis. We find that metal electromigration can drive structural transformation during electrolysis to minimize current crowding in nanoscale geometric constrictions. This electrical phenomenon, acting in combination with electrochemically induced atomic migration, can result in specific structural transformations of the catalyst, with the extent and rate depending on the material, geometry and reaction. Using a series of nanostructure examples, we establish a general framework for evaluating the structural transformations in cathodic metal nanocatalysts and explain specific qualitative trends. In conjunction with catalyst design rules, this mechanistic framework will facilitate the development of nanostructured electrocatalysts with sufficient stability for sustainable applications. The structural stability of electrocatalysts with complex nanoscale morphology, a requirement for their industrial implementation, often remains elusive. Now, a combination of electrical and electrochemical effects is shown to drive specific structural transformations of the catalyst during electrolysis.

The electrochemical urea oxidation reaction (UOR) to N

Shape and surface chemistry control in copper nanoparticle synthesis is an important research area due to a wide range of developing applications of this material in catalysis, energy conversion, sensing and many others. In addition to being an inexpensive and abundant metal, copper is an attractive photocatalyst due to its optical properties in the visible range. Here, we report a facile, tunable and sustainable methodology for synthesizing Pd-seeded Cu nanoparticles with various shapes, including cubes, spheres, raspberry-like particles and cages stabilized with a bilayer of a cationic surfactant in aqueous media. The experimental and theoretical examination of the optical response in the series of synthesized nanoparticles revealed that the low-energy extinction peak is associated with electronic interband transitions in the metal, in contrast to a widely spread attribution of this peak to a plasmonic response in Cu nanoparticles.

We discuss the environmental and energetic benefits of coupling nitrogenous waste treatment with the electrochemical conversion of CO2 to value-added products via direct reduction or electrocarboxylation. In particular, we demonstrate that co-electrolysis of urea or ammonia with CO2 requires significantly lower cell voltages than CO2 electrolyzers relying on the oxygen evolution reaction as an anodic process.

Electrocarboxylation of organic halides represents a CO2 utilization strategy and a green alternative for the synthesis of many industrially relevant carboxylic acids. However, current electrocarbo...

The sensitized photoexcitation of 2-diazocyclopentane-1,3-diones in the presence of THF leads to the insertion of the terminal N-atom of the diazo group into the α-С–Н bond of THF, producing the associated N-alkylhydrazones in yields of up to 63–71%. Further irradiation of hydrazones derived from furan-fused tricyclic diazocyclopentanediones culminates in the cycloelimination of furans to yield 2-N-(alkyl)hydrazone of cyclopentene-1,2,3-trione. By contrast, the direct photolysis of carbocyclic diazodiketones gives only Wolff rearrangement products with up to 90–97% yield.

Electrochemical reduction of benzylic halides represents a convenient route to generating carbanions for their subsequent coupling with CO2 to obtain various carboxylic acids. Despite the industrial prospects of this synthetic process, it still lacks systematic studies of the efficient catalysts and reaction media design. In this work, we performed a detailed analysis of the catalytic activity of a series of different metal electrodes towards electroreduction of benzylic halides to corresponding radicals and carbanions using cyclic voltammetry. Specifically, we screened and summarized the performance of 12 bulk metal cathodes (Ag, Au, Cu, Pd, Pt, Ni, Ti, Zn, Fe, Al, Sn, and Pb) and 3 carbon-based materials (glassy carbon, carbon cloth, and carbon paper) towards electrocarboxylation of eight different benzylic halides and compare it to direct CO2 reduction in acetonitrile. Extensive experimental studies along with a detailed analysis of the results allowed us to map specific electrochemical properties of different metal electrodes, i.e., the potential zones related to the one- and two-electron reduction of organic halides as well as the potential windows where the electrochemical activation of CO2 does not occur. The reported systematic analysis should facilitate the development of nanostructured electrodes based on group 10 and 11 transition metals to further optimize the efficiency of electrocarboxylation of halides bearing specific substituents and make this technology competitive to current synthetic methods for the synthesis of carboxylic acids.

The paper describes results of vegetative tests of active coal as a detoxiсant of herbicide remains in soil on eight varieties of summer rapeseed. The tests were performed with the purpose to align soil fertility on different breeding and test sites. The research is based on attempts to apply coal absorbent as a means of soil detoxication to neutralize herbicides remains in the process of oilseed brassica crops breeding. Several summer rapeseed varieties originated by All-Russian Rapeseed Institute were used as research objects [2,3,5-11]. Similar approaches have not been encountered in literature references available.

Apart from their anti-inflammatory action, COX inhibitors have gathered the interest of many scientists due to their potential use for the treatment and prevention of cancer. It has been shown that cyclooxygenase inhibitors restrict cancer cell growth and are able to interact with known antitumor drugs, enhancing their in vitro and in vivo cytotoxicity. The permutation of hydrophilic and hydrophobic aryl groups in COX inhibitors leads to cardinal changes in the biological activity of the compounds. In the present study, thirteen heterocyclic coxib-like 4,5-diarylfuran-3(2H)-ones and their annelated derivatives&mdash, phenanthro[9,10-b]furan-3-ones&mdash, were synthesized and studied for anti-inflammatory and COX-1/2 inhibitory action and for their cytotoxic activity on the breast cancer (MCF-7) and squamous cell carcinoma (HSC-3) cell lines. The F-derivative of the &ndash, SOMe substituted furan-3(2H)-ones exhibited the best activity (COX-1 IC50 = 2.8 &mu, M, anti-inflammatory activity (by carrageenan paw edema model) of 54% (dose 0.01 mmol/kg), and MCF-7 and HSC-3 cytotoxicity with IC50 values of 10 &mu, M and 7.5 &mu, M, respectively). A cytotoxic effect related to the COX-1 inhibitory action was observed and a synergistic effect with the anti-neoplastic drugs gefitinib and 5-fluorouracil was found. A phenanthrene derivative exhibited the best synergistic effect with gefitinib.

The interaction of 5,5-dialkyl(diaryl)-substituted 4-diazo-3(2H)furanones with Bronsted acids (TFA, TsOH, etc.) causes elimination of nitrogen accompanied by 1,2-nucleophilic rearrangement, giving rise to exclusive formation of 4,5-dialkyl(diaryl)-substituted 3(2Н)-furanones, ring-fused 3(2H)-furanones, and phenanthro[9,10-b]furan-3(2H)-ones in yields of up to 99%. The reaction is a new highly efficient way for the synthesis of multisubstituted 3(2Н)furanones.

This particular study deals with the impact of pre-sowing nanotube-based seed treatment technology on rapeseed (Brassica napus) growth and yield. During the field tests we identified a significant yield increase as a result of applying the pre-sowing nanotube-based seed treatment technology. The main treatment agents were physiologically active nanochips consisting of carrier matrix nanotubes with eliciting activity ("Taunit", "Taunit-M", "Taunit-MD", and graphene). Enriching nanochips with insecticide-fungicide Kruyzer for guaranteed seed protection from crucifer flea allowed to raise the yield up to 8.08 t / ha - 12.28 t / ha.

Rh(II)-сatalyzed reactions of aroyldiazomethanes, diazoketoesters and diazodiketones with α,β-unsaturated δ-aminoesters, in contrast to reactions of diazomalonates and other diazoesters, give rise to the Wolff rearrangement and/or oxidative cleavage of the initially formed N–H-insertion products. These oxidation processes are mediated by Rh(II) catalysts possessing perfluorinated ligands. The formation of pyrrolidine structures, characteristic for catalytic reactions of diazoesters, was not observed in these processes at all.

Protonation of diazodiketones N2C(COR)2 in Bronsted superacids (TfOH, FSO3H, TfOH–SbF5) gives rise to stable and non-reactive O,O-diprotonated at carbonyl oxygens species N2C(C( OH+)R)2, which were studied by means of 1H and 13C NMR. Diazomalonates N2C(CO2Alk)2, contrary to diazodiketones, react with TfOH or HF, releasing nitrogen and producing triflates of oxymalonates TfOCH(CO2Alk)2 or fluoromalonates FCH(CO2Alk)2, respectively. Diazoketoesters N2C(COR)(CO2Alk) react in the same way only with TfOH, but not with HF. The reactions of diazomalonates with arenes ArH (benzene, toluene, xylenes) in TfOH solution yield corresponding Friedel–Crafts reaction products ArCH(CO2Alk)2. According to performed DFT calculations, trication +CH(C( OH+)OMe)2, a possible intermediate, which is derived from protonation of dimethyl diazomalonate, should be the strongest cationic carbon-centered electrophile known up to date.

We present a sacrificial anode-free approach to reductive homocoupling of organohalides that does not require a co-catalyst. In this approach, a divided electrochemical cell with aprotic and aqueous compartments separated by an anion exchange membrane enables coupling of the cathodic homocoupling reaction with anodic oxidation of urea. We show that, in contrast with traditional one-compartment cells relying on sacrificial anodes, the proposed cell configuration maintains stable cell voltage in the course of galvanostatic electrolysis. A synthetic potential of this method was assessed using a series of 13 organic bromides that demonstrated a strong dependence of the reaction outcome on the structure of the organic substrate, more specifically, the dissociation energy of the C–Br bond and the redox properties of formed radicals, which are discussed in detail. While not being suitable for the synthesis of byarylstructures, this method is excellent for C(sp3)-C(sp3) coupling to corresponding dimeric products with up to quantitative yields. Simultaneous electrochemical treatment of nitrogenous waste in the adjacent half-cell provides an additional incentive for wide adaptation of this sustainable synthetic approach.