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81.
《Mendeleev Communications》2023,33(2):249-251
The reactions between Ph3As and ω-bromoalkanoic acids with the length of polymethylene fragment n = 5, 7, 9 afford quaternary arsonium salts. Their treatment with alkali gives biologically active arsenobetaines. Solvent-free reactions of Ph3P or Ph3As with 2,3-dibromopropionic acid lead to the corresponding arsonium and phosphonium salts bearing (CH2)2COOH substituent. 相似文献
82.
《Mendeleev Communications》2023,33(4):466-468
The syntheses and characterization of novel propargyl ethers of N-(hydroxymethyl)nitramines that contain from one to four nitramine units are reported. All nitramine-functionalized ethers were well characterized by IR and multinuclear NMR spectroscopy as well as CHN analysis, and the X-ray crystal structures of two of them are described. For ethers bearing two or three nitramine units, the standard molar enthalpies of formation at 298.15 K were determined from the experimental standard molar energies of combustion in oxygen measured by static bomb combustion calorimetry 相似文献
83.
《Mendeleev Communications》2023,33(2):180-183
A simple one-step synthesis of (NHC)2NiCl2 complexes containing bulky N-heterocyclic carbene (NHC) ligands relies on the C–H metallation of N,N'-diaryl-substituted azolium salts, NHC-precursors, with NiCl2Py2 in the presence of Cs2CO3 and pyridine. This procedure allows one to implement all synthetic manipulations in air. 相似文献
84.
《Mendeleev Communications》2023,33(4):494-496
A new method for selective C(5)–H alkylation of 2-substituted furans with tertiary and secondary alkyl bromides under photoinduced by visible light (∼460 nm) palladium catalysis has been developed. The method is relied on the use of available Pd(PPh3)4 catalyst under mild conditions (30 ± 5 °C, K2CO3 as base), tolerates to various functional groups in furanic substrates and provides from good to excellent yields of alkylated products. 相似文献
85.
《Mendeleev Communications》2023,33(3):387-389
A new method for deoxygenation of fluoroalkyl-substituted alcohols involves derivatization of the hydroxy group with pentafluoropyridine followed by photoredox catalyzed reduction of the obtained hetaryl ethers using γ-terpinene as a source of hydrogen. The initial alcohols can be easily obtained by nucleophilic fluoroalkylation of the corresponding aldehydes. 相似文献
86.
《中国化学快报》2023,34(1):107152
Application of Li-oxygen (Li-O2) battery is in urgent need of bifunctional ORR/OER electrocatalyst. A surface-functionalization CoP/Ti3C2Tx composite was fabricated theoretically, with the optimized electronic structure and more active electron, which is beneficial to the electrochemical reaction. The accordion shaped Ti3C2Tx is featured with large specific surface area and outstanding electronic conductivity, which is beneficial for the adequate exposure of active sites and the deposition of Li2O2. Transition metal phosphides provide more electrocatalytic active sites and present good electrocatalytic effect. The CoP/Ti3C2Tx composite served as the electrocatalyst of Li-O2 battery reaches a high specific discharge capacity of 17,413 mAh/g at 100 mA/g and the lower overpotential of 1.25 V, superior to those of the CoP and Ti3C2Tx individually. The composite of transition metal phosphides and MXene are applied in Li-O2 battery, not only demonstrating higher cycling stability of the prepared CoP/Ti3C2Tx composite, but pointing out the direction for their electrochemical performance improvement. 相似文献
87.
《中国化学快报》2023,34(6):107934
Realizing both a high emission efficiency and luminescence dissymmetry factor (glum) in circularly polarized solution processable organic light-emitting diodes (CP-OLEDs) remains a significant challenge. In this contribution, two chiral phosphorescent liquid crystals based on cyclometalated platinum complexes are prepared, in which the chiral s-2-methyl-1‑butyl group is introduced into the cyclometalating ligand and the mesogenic fragment is attached to the periphery of the ancillary ligand. The platinum complexes exhibit both smectic and chiral nematic phases as evidenced by polarized optical microscopy, differential scanning calorimetry and small-angle X-ray diffraction. Remarkably, a high photoluminescent quantum efficiency of over 78% and clear circularly polarized luminescent signal with gPL of about 10–2 are observed for the complexes. Further, solution-processed CP-OLEDs show maximum external quantum efficiencies (EQE) of over 15% and strong circularly polarized electroluminescent signals with a gEL ≈ 10–2. This research demonstrates that both liquid crystallinity and the number of chiral centers play key roles in improving the chiroptical property, paving the way for a new approach for the design of high-efficiency CPL emitters. 相似文献
88.
《中国化学快报》2023,34(6):107978
Sodium-ion batteries (SIBs) have received significant attention in large-scale energy storage due to their low cost and abundant resources. To obtain high-performance SIBs, many intensive studies about electrode materials have been carried out, especially the cathode material. As various types of cathode material for SIBs, a 3D open framework structural Na3V2(PO4)2F3 (NVPF) with Na superionic conductor (NASICON) structure is a promising cathode material owing to its high operating potential and high energy density. However, its electrochemical properties are severely limited by the poor electronic conductivity due to the insulated [PO4] tetrahedral unit. In this review, the challenges and strategies for NVPF are presented, and the synthetic strategy for NVPF is also analyzed in detail. Furthermore, recent developments of modification research to enhance their electrochemical performance are discussed, including designing the crystal structure, adjusting the electrode structure, and optimizing the electrolyte components. Finally, further research and application for future development of NVPF are prospected. 相似文献
89.
《中国化学快报》2023,34(9):108156-51
Hydrogen evolution from water electrolysis has become an important reaction for the green energy revolution. Traditional precious metals and their compounds are excellent catalysts for producing hydrogen; however, their high cost limits their large-scale practical application. Therefore, the development of affordable electrocatalysts to replace these precious metals is important. Transition metal phosphides(TMPs) have shown remarkable performance for hydrogen evolution and garnered considerable ... 相似文献
90.
《中国化学快报》2023,34(9):108157
This work reported the lanthanide ion (Gd3+) doped tungsten trioxide (Gd-WO3) nanocrystal for remarkable promoted photocatalytic degradation of organic pollutants and simultaneous in-situ H2O2 production. With doped lanthanide ion (Gd3+), Gd-WO3 showed a much broad and enhanced solar light absorption, which not only promoted the photocatalytic degradation efficiency of organic compounds, but also provided a suitable bandgap for direct reduction of oxygen to H2O2. Additionally, the isolated Gd3+ on WO3 surface can efficiently weaken the *OOH binding energy, increasing the activity and selectivity of direct reduction of oxygen to H2O2, with a rate of 0.58 mmol L−1 g−1 h−1. The in-situ generated H2O2 can be subsequently converted to •OH based on Fenton reaction, further contributed to the overall removal of organic pollutants. Our results demonstrate a cascade photocatalytic oxidation-Fenton reaction which can efficiently utilize photo-generated electrons and holes for organic pollutants treatment. 相似文献