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A metal‐free visible‐light‐promoted regioselective trifluoromethylselenolation of electron‐rich heteroarenes has been developed using C–H functionalization. This eco‐friendly, atom‐economical, and easy‐to‐operate protocol provides direct access to a wide range of functionalized SeCF3‐containing heteroarenes in high yields, and is amenable to continuous flow techniques. A radical mechanism was supported by EPR experiments. [ABSTRACT FROM AUTHOR]

Polyoxometalate (POM) compounds constitute a wide family rich of more than several thousand inorganic compounds which can be finely tuned at the molecular level. Considering the high diversity in their structures and properties, the incorporation of such inorganic components into liquid crystalline phases or ionic liquid phases is particularly relevant for the elaboration of functional materials. By adjusting the molecular structures of the anions and the nature of the counter cations, many authors designed different types of mesophases sometimes with application in optoelectronics, or true POM‐based ionic liquids (POM‐ILs with melting temperatures below 100 °C). The latter turn out to be highly interesting for various applications in catalysis, depollution, or protection of the historical heritage. This review focuses on the recent developments in these organic/inorganic hybrid materials, POM‐based ionic liquid crystals and POM‐ILs, and their applications. [ABSTRACT FROM AUTHOR]

Abstract: The demethylation of lignin in ionic liquids (ILs) was investigated by using pure lignin model monomers and dimers together with dioxane‐isolated lignins from poplar, miscanthus, and maize. Different methylimidazolium ILs were compared and the samples were treated with two different heating processes: microwave irradiation and conventional heating in a sealed tube. The conversion yield and influence of the treatment on the lignin structure were assessed by 31P NMR spectroscopy, size‐exclusion chromatography, and thioacidolysis. The acidic methylimidazolium IL [HMIM]Br was shown to be an effective combination of solvent and reagent for the demethylation and depolymerization of lignin. The relatively mild reaction conditions, the clean work‐up, and the ability to reuse the IL makes the described procedure an attractive and new green method for the conversion of lignin to produce phenol‐rich lignin oligomers. [ABSTRACT FROM AUTHOR]

N-Acylated perfluoroalkylated sulfoximines are synthe-sized easily from the corresponding free NH-sulfoximines on reac-tion with acid chlorides. This mild procedure is extended to diacid chlorides for the preparation of dimeric N-bridged sulfoximines and to reactions with chloroformates, carbamoyl chlorides, chlorothio-noformates and thiocarbamoyl chlorides as electrophiles. [ABSTRACT FROM AUTHOR]

Benzo[1,3,2]dithiazole‐1,1,3‐trioxides are bench‐stable and easy‐to‐use reagents. In photoredox catalysis, they generate methyl and perdeuteromethyl radicals which can add to a variety of radical acceptors, including olefins, acrylamides, quinoxalinones, isocyanides, enol silanes, and N‐Ts acrylamide. As byproduct, a salt is formed which can be regenerated to the original methylating agent. Flow chemistry provides an option for reaction scale‐up further underscoring the synthetic usefulness of these methylation reagents. Mechanistic investigations suggest a single‐electron transfer (SET) pathway induced by photoredox catalysis. [ABSTRACT FROM AUTHOR]

The structure of a self-assembled system containing benzoselenadiazole with the corresponding cationic N-methyl salt was determined by X-ray diffraction analysis. The assembly has a distinct tendency to establish intermolecular links in the solid state through secondary intermolecular bonding SeN interactions. In such supramolecular association, the observation of an unusual asymmetric four-member ring [SeN]2with a short contact of 2.573 and a long contact of 2.966 was observed. [ABSTRACT FROM AUTHOR]

Access to original ortho thioether derivatives was achieved through a [3,3]-rearrangement in a one-pot two-step protocol. Several aryl-SCF 3 compounds are reported by variation of the nitrile or of the trifluoroalkyl sulfoxide starting material. The variation of the perfluoroalkyl chain was also possible., (Copyright © 2024, Li et al.)

A selective access to perfluoroalkyl selenoxides, via Oxone® as oxidant or to selenones by using a Polyoxometalate-based Ionic Liquid (POM-IL) as a catalyst for the oxidation step is described. The reaction works with various perfluoralkyl chains and substituents with satisfactory to excellent yields. A two-step one-pot reaction from selenocyanates was performed to gain access to perfluoroalkyl selenoxides. The previously unknown perfluoroalkyl selenoximines family was also prepared with good yields. Having unlocked two strategies for the synthesis of fluoroalkylated Se IV and Se VI compounds, we then evaluated the Hansch-Leo lipophilicity parameters of these groups. Finally, asymmetric aryl perfluoroalkyl selenoximines were resolved to determine their absolute configurations., (© 2023 Wiley-VCH GmbH.)

The electroreduction of SF 6 is shown at ambient temperature in acetonitrile using an array of platinum microelectrodes to improve the electrical detection. Its half reduction potential occurs at -2.17 V vs Fc + /Fc. The exact number of electrons for the full consumption of sulfur hexafluoride was determined and this gas further quantitatively transformed into environmentally benign fluoride anion and sulfur by electrochemical reduction., (Copyright © 2020, Bouvet et al.; licensee Beilstein-Institut.)

A general efficient one-pot synthesis of S-perfluoroalkylated NH-sulfoximines from sulfides has been developed using phenyliodine diacetate (PIDA) and ammonium carbamate. Remarkable rate enhancement with trifluoroethanol was observed, presumably due to H-bonding effects. These mild and metal-free conditions are compatible with -CH 2 F, -CFCl 2 , -CF 2 H, -CF 2 Br, -C 4 F 9 , and -CF 3 groups, in both the alkyl- and aryl series. Based on a 19 F NMR analysis, a λ 6 -acetoxysulfanenitrile intermediate was proposed., (© 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)