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This concept focuses on the application of alternating current (AC) and pulsed electrolysis in Atom Transfer Radical Polymerization (ATRP) for polymer synthesis. AC electrolysis, which oscillates between reduction and oxidation, can be tuned to increase selectivity for a specific reaction pathway, minimize side reactions, and improve product selectivity and reagent conversion. Pulsed electrolysis can also be used to sustain electrochemical reactions in ATRP. The challenges and limitations associated with AC electrolysis are discussed along with an outlook on future developments in polymer synthesis and related applications. A concise overview of recent developments in electro-organic synthesis using AC electrolysis will be provided.

Using as example the [Fe(bpca)(μ-bpca)Gd(NO₃)₄]×4CH₃NO₂×CH₃OH system, where Hbpca=bis(2-pyridilcarbonyl)amine), we perform the analysis of bonding components inside the d and f coordination units and between molecular entities from crystal. Aside the nominal long-range interactions between molecular components of the crystal, we considered that the bonding inside the coordination units is also not a covalent regime. We performed Density Functional Theory (DFT) calculations, with plane-waves (PW), in band-structure mode, and with atom-centred bases, by molecular procedures. Observing that the PW-DFT frame is free of basis set superposition errors, which is an important methodological hint underlined here, we estimated various non-covalent terms. E.g. the interaction between inversion-related FeGd units amounts -394.47 kcal/mol, only about -37 kcal/mol being due to Coulomb effects, the remainder being assignable to dispersion forces. One FeGd binuclear interacts with the closest methanol molecule by -9.30 kcal/mol and by -36.57 kcal/mol with the set of four nitromethane molecules. The energy decomposition analysis of molecular calculations showed, aside the expected ionic character (about 82 % of the total cohesion energy of lanthanide ion in molecule), the important role of empty 5d orbitals. The d virtuals are contributing with 68.4 kcal/mol, out of 97.15 kcal/mol quantity estimated as ligand-to-metal donor-acceptor effects.

Pickering interfacial biocatalysis (PIB), where biocatalysts stabilize emulsions through carrier coupling or polymer grafting, has emerged as a powerful platform for organic synthesis due to its ability to accommodate water-insoluble substrates within enzymatic cascade reactions. PIB provides a large interfacial area for two-phase reactions, reducing diffusional resistance and enhancing transformation efficiency. The performance of PIB relies heavily on enzyme-particle conjugates, which serve a dual function: stabilizing the emulsion and acting as the active biocatalysts in the system. In this Concept, we discuss the latest advancements, current challenges, and future directions in the development of protein-particle conjugates for PIB.

Azoloazine derivatives are known as promising small molecules that are potentially able to counteract a broad spectrum of RNA viruses including SARS-CoV-2. However, a pool of synthetic pathways to provide convenient structural modification of such compounds without de novo construction of the heterocyclic scaffold is rather limited so far. This work proposes an approach to the direct C(sp²)−H functionalization of azolopyrimidine substrates with aromatic thiol residues, mediated by the iodine/persulfate reagent system. The reported herein sulfenylation protocol has afforded a series of previously undescribed azolopyrimidine-based thioethers obtained in yields of up to 87 %. Applicability of the approach to the selenium-centered synthons has been demonstrated as well. Besides, the in silico study with regard to the achieved cross-coupling products has suggested the possible affinity to the SARS-CoV-2 main protease (M^pro), as follows from the conducted pharmacophore search and the molecular docking experiments. As a result, the developed synthetic transformation is expected to be of utility in the design of novel antiviral agents based on small azaheterocyclic molecules.

The natural carbon cycle cannot mitigate and recycle the excess CO₂ in the atmosphere, leading to a continuous rise in the global temperature. Electrochemical conversion of CO₂ is one of the useful methods to utilise this anthropogenic CO₂ and convert it into value-added chemicals. However, this process suffers the challenges of product selectivity and good Faradaic efficiency. In our current work, we report the role of Zn-doping in the 2D-Nanosheet of Cu₂(OH)₃(NO₃)-a pre-catalyst that undergoes the in-situ transformation into a metallic state along with surface reconstruction. Our studies show, in the aqueous medium, the optimum amount of Zn plays a crucial role in the production of ethanol with the Faradaic efficiency of ∼45.2 % though C−C coupling. Temperature-programmed desorption studies conclude that Zn increases the product selectivity for CO adsorption on Cu₂(OH)₃(NO₃) nanosheets, further facilitating the C−C coupling at higher negative potential. The detailed XPS studies also reveal that the in-situ conversion of Cu²⁺ to Cu⁰ and Cu⁺ at negative potential contributes to the production of C₂ products. The post-catalytic microstructural and spectroscopic studies converge to this point that the cumulative effect of oxidation state, surface reconstruction, as well as the presence of Zn modulate the overall Faradaic efficiency for ethanol formation.

Zr-monosubstituted polyoxometalates (Zr-POMs) of the Keggin (Bu₄N)₈[{PW₁₁O₃₉Zr(μ-OH)}₂] (Zr-K), Lindqvist (Bu₄N)₆[{W₅O₁₈Zr(μ-OH)}₂] (Zr-L), and Wells-Dawson (Bu₄N)₁₁H₃[{P₂W₁₇O₆₁Zr(μ-OH)}₂] (Zr-WD) structures are capable of heterolytic activation of the environmentally benign oxidant tert-butyl hydroperoxide (TBHP) and catalyze epoxidation of alkenes and oxidation of alcohols to carbonyl compounds. Catalytic activity of corresponding Ti-POMs is much lower. Among Zr-POMs, Zr-K revealed higher epoxide yields. All Zr-POMs do not catalyze unproductive TBHP degradation, and epoxide yields with both aqueous and anhydrous TBHP are generally higher than with aqueous H₂O₂. Regioselectivity of the Zr-K-catalyzed limonene epoxidation with TBHP is different from that with H₂O₂: the more substituted and nucleophilic double bond is preferably epoxidized, pointing to an electrophilic oxygen transfer mechanism. The oxidation rates are first order in catalyst (Zr-K) and substrate (cyclooctene or cyclohexanol) and show a saturation behavior with increasing concentration of TBHP. Studies by HR-ESI-MS, ATR-FT-IR, and ³¹P NMR spectroscopic techniques implicated the formation of zirconium alkylperoxo species upon interaction of Zr-POMs with TBHP. HR-ESI-MS revealed the existence of monomeric and dimeric alkylperoxo complexes, [{PW₁₁O₃₉Zr}((CH₃)₃COO)]^4- and [{PW₁₁O₃₉Zr((CH₃)₃COO)}₂]^8-, with predomination of the former, which is most likely the active species responsible for the selective oxidations.

The aim of this study is to investigate the activity of KIT-6 supported nickel (Ni) and cobalt (Co) catalysts, and the effect of Co incorporation to the Ni@KIT-6 catalyst in the formic acid (FA) dehydrogenation. Ni and Co are inexpensive and readily available non-noble transition metals that are considered ideal for dehydrogenation reactions due to their high activity against C-C and C-H bond breaking. In this study, KIT-6 supported catalysts were tested for hydrogen production from FA in a conventionally heated packed-bed continuous-flow system. N₂ adsorption-desorption isotherms of the samples were found to be consistent with Type-IV according to the International Union of Pure and Applied Chemistry (IUPAC) classification. The introduction of metal loading resulted in the preservation of the mesoporous structure of the support material. X-ray diffraction (XRD) patterns of the catalysts exhibited the characteristic amorphous silica structure. Diffuse Reflectance Infrared Fourier Transform Spectroscopy (DRIFT) analysis, Lewis acidity of Co-based catalysts was found to be higher than the Ni-based catalysts. The complete formic acid conversion was observed at 200-350 °C. The highest H₂ selectivity was obtained with the 3Ni@KIT-6 catalyst. The Co-based catalysts exhibited relatively lower catalytic activity, which was linked to increased coke formation within these catalysts.

An unexpected course of the reaction of hexafluorocumyl alcohol dilithium derivative 2 with N-(t-butylsulfenyl)phthalimide (3) has been presented. The process proceeded under mild conditions and resulted in previously undescribed chiral spiro-system- 3',3'-bis(trifluoromethyl)-3H,3'H-1,1'-spirobis(isobenzofuran)-3-one (5) as the only product. A detailed spectral analysis of the product has been provided, and mechanistic aspects have been investigated. Attempts to separate the enantiomers of compound 5 using a semipreparative HPLC method with a chiral stationary phase column have been described. The repeatability of the reaction using analogs of alcohol 4 has also been tested. DFT calculations of absolute configuration assignment have been performed successfully.

Atomically ordered intermetallic Pt-based nanoparticles, recognized as advanced electrocatalysts, exhibit superior activity for the oxygen reduction reaction (ORR) in fuel cell cathodes. Nevertheless, the formation of these ordered structures typically necessitates elevated annealing temperatures, which can accelerate particle growth and diminished reactivity. In this study, we synthesized carbon-supported platinum-cobalt intermetallic compounds (PtCo-IMCs) with sub-4 nm particle sizes and uniform distribution. These catalysts, characterized by high platinum content and exceptional ORR activity, are specifically tailored for heavy-duty vehicle (HDV) applications. The PtCo-IMCs exhibited significantly enhanced catalytic performance and durability compared to conventional Pt-based catalysts, utilizing platinum nanoparticles as nucleation sites to promote growth. This method effectively retained smaller particle sizes while achieving a higher degree of ordering and alloying during high-temperature annealing. Optimization of the annealing temperature resulted in peak activity and stability at 800 °C. The mass activity (MA) of the PtCo-800 catalyst was 2.7-fold and 1.8-fold that of the commercial Pt/C and disordered PtCo catalysts, respectively. Additionally, the single cell employing the PtCo-800 catalyst showed a minimal voltage loss of only 27 mV at a current density of 2 A cm⁻² after 30,000 cycles of the accelerated durability test (ADT), underscoring its long-term stability. This work provides an efficient method for the preparation of high loading ORR electrocatalyst with excellent durability.

The poorly understood factors controlling the reactivity and selectivity (both stereo- and enantioselectivity) of catalyzed Diels-Alder reactions involving cyclobutenones as dienophiles have been analyzed in detail by means of Density Functional Theory calculations. To this end, the reactions with cyclopentadiene and furan as dienes and 3-(methoxycarbonyl)cyclobutenone catalyzed by Corey's chiral oxazaborolidium ion (COBI) have been selected and compared to their analogous uncatalyzed transformations. The combined Activation Strain Model of reactivity and Energy Decomposition Analysis methods have been used to quantitatively understand the acceleration and selectivity induced by the catalyst in this reaction.