In the past decade, selenocyclization has been extensively exploited for the preparation of a wide range of selenylated heterocycles with versatile activities. Previously, selenium electrophile-based and FeCl-promoted methods were employed for the synthesis of selenylated benzoxazines. However, these methods are limited by starting material availability and low atomic economy, respectively. Inspired by the recent catalytic selenocyclization approaches based on distinctive pathways, we rationally constructed an efficient and greener double-redox catalytic system for the access to diverse selenylated benzoxazines. The coupling of I/I and Fe/Fe catalytic redox cycles enables aerial O to act as the driving force to promote the selenocyclization. Control and test redox experiments confirmed the roles of each component in the catalytic system, and a PhSeI-based pathway is proposed for the selenocyclization process.
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http://dx.doi.org/10.3390/molecules27217386 | DOI Listing |
Proton insertion mechanism with fast reaction kinetics is attracting more and more attention for high-rate and durable aqueous Zn─MnO batteries. However, hydrated Zn insertion reaction accompanied with Jahn-Teller effect and Mn disproportionation generally leads to sluggish rate capability and irreversible structure transformation. Here, carboxyl-carbon nanotubes supported α-MnO nanoarrays (C─MnO) cathode is successfully fabricated by a convent grinding process for high-performance Zn batteries.
View Article and Find Full Text PDFAngew Chem Int Ed Engl
March 2025
Central South University, School of Metallurgy and Enviroment, No. 932, Lushan Road,, Changsha city, Hunan Province, 410083, Changsha, CHINA.
Activated by the Li-O-Li configuration with nonbonding O2p state (lO2p), anionic redox reaction (ARR) in Li-rich layered oxides (LLOs) contributes to additional capacity but exhibits significant irreversibility, leading to severe surface oxygen loss. Herein, surface nonbonding oxygen state (SNBOS) is regulated by the integrated surface structure engineering to suppress surface oxygen loss and enhance the reversibility of ARR. On the outermost layer, the conversion of layered structure into a LiLaO2 layer and spinel phase structure eliminates lO2p, thereby preventing the activation of ARR and suppressing side reaction between electrolyte and oxidized oxygen ions.
View Article and Find Full Text PDFJ Mater Chem A Mater
February 2025
Department of Engineering, University of Cambridge 17 Charles Babbage Road CB3 0FS Cambridge UK
Titanium niobium oxides (TNOs) are attractive anode materials for high power density Li-ion batteries. However, the details of capacity storage in TNOs are not fully understood today as it depends on the Ti and Nb composition and their changes in the oxidation state. This is further complicated by a wide variation in gravimetric capacities reported in the literature for TNO anodes.
View Article and Find Full Text PDFBiogeochemistry
March 2025
Institute of Marine and Coastal Science, Rutgers, The State University of New Jersey, New Brunswick, NJ USA.
Unlabelled: Alongside global climate change, many freshwater ecosystems are experiencing substantial shifts in the concentrations and compositions of salt ions coming from both land and sea. We synthesize a risk framework for anticipating how climate change and increasing salt pollution coming from both land and saltwater intrusion will trigger chain reactions extending from headwaters to tidal waters. Salt ions trigger 'chain reactions,' where chemical products from one biogeochemical reaction influence subsequent reactions and ecosystem responses.
View Article and Find Full Text PDFMaterials (Basel)
March 2025
Faculty of Chemistry, Northeast Normal University, Changchun 130024, China.
In this paper, the natural waste pinecone as a carbon precursor for the generation of satisfactory sulfur host materials in lithium-sulfur batteries was realized by introducing molybdenum carbide nanoparticles into the derived carbon structure. The conductive pinecone-derived carbon doped with N, O reveals an expansive specific surface area, facilitating the accommodation of a higher sulfur load. Moreover, the integration of MoC nanoparticles also significantly enhances its chemical affinity and catalytic capacity for polysulfides (LiPSs) to alleviate the shuttle effect and accelerate sulfur redox conversion.
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