Chinese Journal of Chemistry最新文献

Photocatalytic aerobic oxidative desulfurization (PAODS) is a sustainable alternative technology to traditional, energy-intensive fuel desulfurization methods. Nonetheless, its advancement is hindered by the notable challenge of inadequate electron-hole separation efficiency within the existing catalytic systems. Herein, a Janus 2D/2D heterostructure composed of Co₃O₄ and CoMoO₄ is reported for the PAODS of thiophenic sulfides. Through a combination of detailed experimental characterizations and density functional theory (DFT) calculations, we elucidate the formation of a type II p-n heterojunction in the catalyst, significantly enhancing electron-hole separation through electric field force and reducing the possibility of electron-hole recombination due to the spatial separation of redox centres. The photocatalyst exhibits exceptional activity and demonstrates an impressive performance of 10.4 mmol·g^–1·h^–1 in the oxidation of dibenzothiophene (DBT). Moreover, the photocatalyst demonstrates profound desulfurization capabilities in real diesel, reinforcing its promising prospects for industrial application. These discoveries provide invaluable insights, both scientifically and practically, towards the development of advanced photocatalysts for PAODS processes.

The pursuit of advanced sodium-ion batteries (SIBs) has been intensified due to the escalating demand for sustainable energy storage solutions. A W-doped P2-type layered cathode material, Na_0.67Ni_0.246W_0.004Mn_0.75O₂ (NNWMO), has been developed to address the limitations of traditional cathode materials. Compared to the pristine Na_0.67Ni_0.25Mn_0.75O₂ (NNMO), NNWMO exhibits improved reversible capacity, excellent cycle performance, and remarkable rate performance. It can deliver an increased discharge capacity of 142.20 mAh/g at 0.1 C, with an admirable capacity retention of 80.5% after 100 cycles at high voltage. In situ XRD results demonstrate that the rivet effect related to the strong W—O bonds inhibits irreversible phase transition and enhances structural reversibility during charge/discharge processes. High-resolution scanning transmission electron microscopy and X-ray diffraction results confirm successful lattice doping of W⁶⁺ and increased layer spacing, contributing to favorable sodium ion diffusion kinetics. Density-functional theory (DFT) calculation results further reveal that the smoother Na⁺ ion diffusion dynamics is attributed to the reduced migration energy barrier of Na⁺ with the insertion of W⁶⁺. This study provides valuable insights into the design of high-performance cathode materials for next-generation SIBs, showcasing the potential for more efficient, stable, and enduring energy storage solutions.

A catalyst-free and additive-free ring-opening reaction of polyfluoroalkyl peroxides, triethylenediamine (DABCO), and 1,2-dichloroethane (DCE) has been developed for the defluorinative synthesis of structurally diverse piperazines featuring a fluoroenone framework and a N-chloroethyl-substituent with high Z-stereoselectivity. The success of this three-component reaction is attributed to the in situ generation of an active 1-(2-chloroethyl)-1,4-diazabicyclo[2.2.2]octan-1-ium (DABCO·DCE) salt, which judiciously acts as a formal N-(2-chloroethyl)piperazine equivalent in the defluorinative coupling with less-studied aliphatic fluorinated substances. Impressively, this reaction accomplishes multi-activation of robust C(sp³)-F, C(sp³)-Cl, C(sp³)-O, and C(sp³)-N bonds in a one-pot process, offering a practical platform for the late-stage functionalization of complex molecules. Furthermore, the resulting products can not only serve as versatile building blocks for the synthesis of fluorinated heterocycles, but also undergo C—Cl bond displacement transformations with N-, O-, and S-nucleophiles.

As one of the famous traditional Chinese herbal medicines, Fritillariae Cirrhosae Bulbus (FCB) is widely used in the prevention and treatment of respiratory diseases and has the best curative effect among the known fritillarias medicines. Due to the variety, complex sources, similar appearance and shape, it is difficult to distinguish FCB with high curative effect (h-FCB) from other common fritillarias (c-FCB) in the market. In this paper, a very simple chemiresistor is used to identify FCB from three commonly used fritillarias drugs. The sensors are fabricated by anisotropic electrically conductive metal-organic framework (cMOF) thin film Cu₃(HHTP)₂ (Cu-HHTP_[001] and Cu-HHTP_[100]) as active materials owing to their ability to detect specific groups of volatile organic compounds (volatolomics) as the functional motifs of chemiresistor. As a result, the sensors show orientation-dependence identification ability to FCB. Cu-HHTP_[001]- based sensor shows the highest response (344.17%) to 0.5 g h-FCB powder volatiles among its three other c-FCB which is much higher than Cu-HHTP_[100] (135.50%). Ultimately, Cu-HHTP_[001] can realize the identification of FCB with an accuracy of 97.2% in a simple and real-time manner.

A copper-catalyzed cyanation/diarylmethylation of formamides has been developed for the synthesis of α-cyano functionalized tetra-substituted olefins by utilizing para-quinone methides (p-QMs) and trimethylcyanosilane as functionalization sources. Various kinds of p-QMs and formamides are well tolerated, delivering the desired products with 72%—94% yields, demonstrating broad functional group tolerance. Notably, the reaction does not require noble metals and proceeds regioselectively under mild conditions. Based on step-by-step control experiments, Hammett studies and DFT calculation, a plausible mechanism is proposed.