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Layered double hydroxides (LDHs) of various compositions, i.e. Mg–Al, Mg–Mn–Al, are applied as the precursors of metal oxides for the preparation of N-doped carbon materials via chemical vapour deposition (CVD) with acetonitrile (as carbon and nitrogen source) at 600 and 700 °C. The use of Mn-containing LDHs for the preparation of the carbon materials is a novelty. The impact of transition metal species, i.e. MnxOy, in a blend of metal oxides derived from LDHs on the amount of carbon deposit and its composition, morphology, textural and capacitive properties is investigated. Mn-containing species occurring in a mixture of metal oxides enhance the quantity of carbonaceous product compared to those derived from Mg–Al LDHs. Thermally heated Mg–Mn–Al LDHs contain structural defects due to manganese oxides, which promote the formation of carbon deposit, especially higher production of amorphous carbons. The addition of Mn into Mg–Al LDHs matrix leads to carbon particles with increased N-doping and enhanced volume of mesopores. Furthermore, graphitic domains occurring in the carbon materials obtained with Mg–Mn–Al LDHs are thicker than those in the corresponding samples obtained with Mg–Al LDHs as Mn-containing species influence the concentration and location of N-containing groups in graphitic array. The specific capacitance of the carbon materials produced by CVD with the compounds derived from Mg–Al LDHs or Mg–Mn–Al LDHs is comparable (20–25 μF cm−2). The formation of electrical double layer at electrode/electrolyte interface is easier for the carbon materials prepared at 700 °C than for the carbon materials prepared at 600 °C. The maximum charge is stored either in the shallow parts of carbon particles for the former, as they contain bottleneck mesopores, or in the deep parts of carbon particles for the latter, as they contain slit-shaped mesopores. Graphical abstract

Protein arylation has attracted much attention for developing new classes of bioconjugates with improved properties. Here, we have systematically evaluated 2-sulfonylpyrimidines as covalent warheads for the mild, chemoselective and metal free cysteine S-arylation. 2-sulfonylpyrimidines react rapidly with cysteine, resulting in stable S-heteroarylated adducts at neutral pH. Fine tuning the heterocyclic core and exocyclic leaving group allowed predictable SNAr reactivity with model tripeptide glutathione in vitro, covering 9 orders of magnitude. We achieved extremely fast chemo- and regio- specific arylation of a mutant p53 protein, and confirmed arylation sites by protein X-ray crystallography. Hence, we report the first example of a protein site specifically S-arylated with iodo-aromatic motifs. Overall, this study provides the most comprehensive structure-reactivity relationship to date on heteroaryl sulfones, and highlights 2-sulfonylpyrimidine as a synthetically tractable and protein compatible covalent motif for targeting reactive cysteines, expanding the arsenal of tunable warheads for modern covalent ligand discovery.

Differences in the activity of Pd/WO3 and Pd/MoO3 (Pd loading 0.4–4 wt%) catalysts in competitive hydrogenations of the C C and C O groups in polyfunctional reagents have been studied as a function of two effects: (1) the in situ formation of hydrogen bronzes, HxWO3 and HxMoO3, and (2) the electronic interaction between the supports and the metallic Pd. The cinnamaldehyde (CAL), furfural (FU) and 5-hydroxymethylfurfural (HMF) were hydrogenated under mild reaction conditions. The formation of hydrogen bronzes in Pd/WO3 and physical mixture of Pd/WO3 with supporting WO3 oxide upon exposure to H2 was also studied using the gas flow-through microcalorimetry. In both Pd/MoO3 and Pd/WO3 catalysts, the electronic interactions contributed to the promotion of selectivity toward the C O hydrogenation in CAL and FU, yet in Pd/MoO3 this effect was much more pronounced. On the other hand, apart from increasing the overall reaction rate, the formation of hydrogen bronzes remarkably enhances the C C hydrogenation in CAL, as well as the decarbonylation of FU to furan and hydrogenolysis of C–OH in HMF to 5-methylfurfural. The bronze effects are significantly stronger in HxWO3, compared to HxMoO3, which may be related to higher H-species mobility and weaker H-bonding in the W–O–H (54 kJ/mol H2) than in the Mo–O–H (100 kJ/mol H2). This may also explain very high tendency of Pd/WO3 to furan ring hydrogenation in FU and HMF as well as almost selective (>98%) hydrogenation of furfuryl alcohol to tetrahydrofurfuryl alcohol.

A robust and versatile protocol for synthesis of 1-monosubstituted and 1,4-disubstituted 1H-1,2,3-triazoles was established under continuous flow conditions using copper-on-charcoal as a heterogeneous catalyst. This methodology allowed for the synthesis of a diverse set of substituted 1,2,3-triazoles with good functional group tolerance and high yields. 2-Ynoic acids were also used as small-chain alkyne donors in a decarboxylation/cycloaddition cascade, allowing gaseous reagents to be bypassed, delivering desired triazoles in high yields. The developed methodology was used to synthesize an antiepileptic agent, rufinamide, which was obtained in 96% isolated yield.

Poly(methylvinylsiloxane) (V3 polymer) obtained by kinetically controlled anionic ring-opening polymerization of 1,3,5-trimethyl-1,3,5-trivinylcyclotrisiloxane was cross-linked with various amounts of 1,3,5,7-tetramethylcyclotetrasiloxane (D4 H) in w/o high internal phase emulsions (HIPEs). PolyHIPEs thus prepared differed in the polymer cross-linking degree, which affected their porous morphology and total porosity. The obtained V3 polymer-based polyHIPEs were applied as matrices for the incorporation of Pd from the Pd(OAc)2 solution in tetrahydrofuran. This process involved the conversion of Si-H groups remaining in the polymer networks and resulted in the formation of crystalline, metallic Pd in the systems. Mean sizes of the generated Pd crystallites were lower in polyHIPEs of higher than in those of lower polymer cross-linking degrees and porosities (∼5 nm vs ∼8 nm, respectively). The Pd-containing polyHIPEs showed activity in catalytic hydrogenation of the triple carbon-carbon bond in phenylacetylene giving the unsaturated product, styrene with a selectivity of ca. 80%. To the best of our knowledge, this is the first work devoted to polysiloxane-based polyHIPEs with dispersed metallic particles.

The paper reports on the solvent and the substituent effects in hydrogenation of aromatic ketones (acetophenone and its derivatives) in the presence of Ru catalyst supported on functionalized gel-type methacrylate-styrene resin under very mild conditions (1 bar H2, 40 °C). The investigated solvents included methanol, 2-propanol, tetrahydrofuran, toluene, isooctane, and cyclohexane, with and without addition of water. The best catalytic activity was obtained in biphasic solvent system consisting of isooctane/water (1:1). In methanol and 2-propanol the beneficial role of water was observed. The effects are discussed in terms of solvent protic/aprotic and polar/apolar properties. The impact of substituents depended on their electron-donating/withdrawing character, and on the position on the aromatic ring of acetophenone. The presence of electron donating substituents tended to increase the reaction rate, and the electron withdrawing group slowed down the process. Steric effect was observed for methylacetophenone isomers with CH3 group at ortho, meta and para positions.