New Journal of Chemistry最新文献

The reaction between the designed benzoxadiazole-functionalized diamine ligand BOSA(NH₂)₂ and Pt(DMSO)₂Cl₂ under ambient atmosphere exclusively yields the carbamic acid–platinum complex BOSA(NH₂)(NHCOOH)PtCl₂, with no experimental evidence for the formation of the non-carboxylated analogue BOSA(NH₂)₂PtCl₂. High-resolution mass spectrometry (HR-MS) confirms the rapid in situ generation of the carboxylated ligand BOSA(NH₂)(NHCOOH) in solution. Density functional theory (DFT) calculations elucidate that CO₂ activation proceeds via either an intramolecular or a solvent-mediated pathway. This study demonstrates that pre-association of CO₂ with the diamine ligand can be the decisive factor in platinum complex synthesis, directly leading to amino acid-based platinum complexes like BOSA(NH₂)(NHCOOH)PtCl₂.

Norfloxacin (NOR) is a common fluoroquinolone antibiotic which is difficult to completely remove through traditional water treatment methods. In this study, a cobalt-doped lignin-based biochar catalyst (CoBC700) was prepared through impregnation and one-step pyrolysis. CoBC700 was coated with well-dispersed multivalent cobalt species, which activated PMS to achieve 95.98% removal of NOR within 30 minutes, with a rate constant reaching 0.3642 min⁻¹, which was significantly higher than that for CoBC550 and CoBC850. Quenching experiments and EPR analysis indicated that NOR was mainly removed by a non-free radical pathway (¹O₂), with the SO₄˙⁻ playing a minor role. The redox cycling of Co⁰/Co²⁺/Co³⁺, in synergy with carbon defects, promoted interfacial electron transfer and selective PMS activation. The system exhibited good stability in the pH range of 3–9, and maintained a removal efficiency of 81.98% after five cycles. Combining DFT calculations and LC–MS, the possible degradation pathways of NOR were proposed. Toxicity assessment showed that the toxicity of most intermediates was lower than that of NOR. This Co-defect synergy strategy provides a pathway to design efficient and environmentally friendly PMS activators.

Typical cast explosives TNT and DNAN face problems during use, and researchers have conducted extensive research to find alternatives to TNT. However, relatively little research exists on fluorine-containing cast explosives. Fluorine has a stronger oxidation ability and a higher density than oxygen atoms and can form hydrogen bonds with adjacent hydrogen atoms, effectively reducing compound sensitivity and improving stability. The synergistic effect of the fluorine element and aluminum powder in aluminum-containing explosives improves the combustion efficiency of aluminum powder. Nonetheless, the intermolecular forces of fluorinated fused cast carrier explosives are weak and volatile, which is unfavorable for fused cast carrier explosives. Therefore, in this study, –NH₂-functionalized fluorinated fused cast carrier explosives were used to increase intermolecular forces, and two fluorinated nitroaniline-fused cast carrier explosives, 5-fluoro-3-methyl-2,4-dinitrophenylamine (DFDNTN) and 5-fluoro-2,4-dinitro-3-(trifluoromethyl)aniline (PFDNTN), were successfully synthesized. The weightlessness phenomenon has been alleviated compared with that in 1,5-difluoro-3-methyl-2,4-dinitrobenzene and 1,5-difluoro-2,4-dinitro-3-(trifluoromethyl)benzene. The melting points are 127.5 °C and 100 °C. The detonation velocities and pressures of DFDNTN are 7335 m s⁻¹ and 23.2 GPa, respectively (IS = 35 J and FS > 360 N); those of PFDNTN are 8136 m s⁻¹ and 30.4 GPa, respectively (IS > 40 J and FS > 360 N). They are expected to become melt carrier explosives to replace TNT.

A Rh(III)-catalyzed annulation has been developed for the synthesis of quinazolines via site-selective C–H activation of aryl ketones with dioxazolones. The reaction proceeds under mild, redox-neutral conditions and does not require pre-installed directing groups. An in situ generated transient directing group derived from hydroxylamine-O-sulfonic acid (HOSA) enables selective C–H activation. This method converts readily available aryl ketones into structurally diverse quinazolines in moderate to excellent yields.

A template-assisted approach was employed to synthesize a MOF-on-MOF derived catalyst for the selective oxidation of 5-hydroxymethylfurfural (5-HMF) to produce 2,5-furandicarboxylic acid (FDCA). Characterization revealed that the catalyst forms a cobalt–manganese metal oxide composite phase with a hierarchical porous structure and uniformly distributed Co/Mn active sites. The oxygen vacancies work together with the Lewis acid sites to gradually oxidize the hydroxyl and aldehyde groups in 5-HMF. In the context of reaction conditions that have been identified as optimal (140 °C, 6 h, 50 mg catalyst, 5.88 mol L⁻¹ H₂O₂), the yield of FDCA was 87.55%, accompanied by 5-HMF conversion rate of 98.66%. The catalyst exhibited exceptional cycling stability, sustaining an FDCA yield exceeding 75% across five cycles. Mechanism studies indicate that the Co–Mn bimetallic synergistic effect optimizes the reaction pathway through electron transfer and oxygen species activation, while the microporous structure prolongs the residence time of intermediates through confinement effect, promoting multi-step oxidation. Compared with the single-metal MOFs derived catalysts, this catalyst has significantly improved adsorption performance and oxidation efficiency, providing an efficient solution for the green synthesis of the bio-based polyester monomer FDCA.

Amidst oil scarcity and surging energy requirements, renewable lignocellulosic biomass stands out as a sustainable substitute. However, the complex interlinkages of lignin pose a barrier to its valorization. In a mild two-step protocol, 2-phenoxy-1-phenylethanol is first oxidized to the corresponding ketone, which then undergoes DBU-promoted C–O bond cleavage. Through the metal-free DBU-catalyzed method, acetophenones and phenols are obtained with high efficiency, which paves the way for the high-value utilization of lignin.

Notwithstanding consistent advancements in CO₂ upgrading and recycling using diverse catalytic methodologies, the production of intricate goods, such as sugars, remains unexamined. L-Erythrulose is a natural keto sugar utilized for various purposes, including natural tanning, streak mitigation, prolonged coloration, and moisturizing properties, making it prevalent in the cosmetic industry. This study presents the innovative development of a tandem catalyst system comprising an S-modified metalloporphyrin and an expanded-structure metalloporphyrin, with a thorough theoretical exploration of the reaction pathway for converting CO₂ to L-erythrulose. To systematically assess the catalytic efficiency of the catalyst, the stability, catalytic activity, product selectivity, and reactivity characteristics during the reaction process have been analyzed using DFT calculations, with the objective of providing theoretical support for the optimal design and performance enhancement of catalysts in carbon dioxide conversion applications. Of the catalysts examined, four demonstrated effective electrocatalysis for the production of L-erythrulose: Fe–SPor–CoRh–SN₅TPor, Fe–SPor–CoIr–SN₅TPor, Co–SPor–CoRh–SN₅TPor, and Co–SPor–CoIr–SN₅TPor. This work proposes an effective electrocatalytic synthesis of L-erythrulose from CO₂ as a precursor for its production. This study broadens the spectrum of product complexity attainable by the electrocatalytic conversion of CO₂, which has been effectively transformed into essential sugars.

Conventional chemotherapy agents such as doxorubicin are frequently constrained by poor tumor selectivity and severe adverse effects, including cardiotoxicity. In this study, we evaluate the natural anthraquinone compound carminic acid (CA) as a safer multifunctional anticancer candidate. Molecular docking simulations indicated that, owing to its anthraquinone core and structural similarity to doxorubicin, CA may exert comparable anticancer mechanisms, including DNA interaction via topoisomerase I and II inhibition, G-quadruplex DNA binding, and photodynamically induced reactive oxygen species (ROS) generation. Experimental analyses confirmed that CA intercalates into DNA and induces structural damage. Furthermore, CA exhibited strong photosensitizing activity, producing ROS under light irradiation, as demonstrated using a newly developed dot blot-based ROS detection assay. To enhance tumor selectivity and therapeutic efficacy, CA was loaded into folic acid-functionalized mesoporous silica nanoparticles (CA@FA-MSNs), enabling pH-responsive drug release. Drug release was significantly higher under acidic conditions than at physiological pH (7.4), consistent with tumor microenvironment targeting. In vitro cytotoxicity assays against HeLa and K-562 cancer cell lines revealed enhanced cytotoxicity toward HeLa cells following folic acid conjugation, attributed to receptor-mediated uptake. Targeted cellular delivery was further supported by the strong intrinsic red fluorescence of CA@FA-MSNs, allowing real-time visualization of intracellular accumulation. A key finding is the fluorescence resonance energy transfer (FRET) interaction between CA and FA, characterized by a 62.2% spectral overlap and stabilized by hydrogen bonding at a distance of 2.25 Å. This interaction results in fluorescence quenching in the carrier state, while enabling ratiometric monitoring of drug release in live cells. Overall, the CA@FA-MSNs platform demonstrates enhanced anticancer efficacy through targeted delivery and light-activated ROS production, highlighting its potential as a multifunctional therapeutic system with integrated FRET-based tracking capability.

Sugarcane bagasse waste was valorized as a precursor to synthesize activated carbon (AC) for supercapacitor electrodes. The ACs were prepared using H₃PO₄ (1–4 mol L⁻¹) followed by thermal treatment at 700 °C, yielding AC-1, AC-2, and AC-4. Among them, AC-4 exhibited the best electrochemical performance. SEM and TEM analyses showed a rough, porous morphology with a surface area of 790.5 m² g⁻¹, micropore area of 497.7 m² g⁻¹, and micropore volume of 0.23 cm³ g⁻¹. FTIR, Raman, and XPS revealed functional groups and aromatic structures enhancing conductivity and electrolyte interaction. AC-4 showed moderate structural disorder with balanced graphitic/amorphous phases. In a three-electrode cell, it delivered a specific capacitance of 266 F g⁻¹, while in a coin cell, it reached 33.9 F g⁻¹ at 0.1 A g⁻¹. It retained 82.41% capacitance after 14 500 cycles and achieved 267.69 W kg⁻¹ power and 1.15 Wh kg⁻¹ energy density, confirming its promise for sustainable energy storage.

The discharge of antibiotics into the environment has emerged as a pressing global issue. In particular, the removal of refractory mixed antibiotics requires advanced technologies with high adsorption efficiency and powerful degradation ability. In this study, we synthesized a heterogeneous core–shell Fe₃O₄@C catalyst as an efficient microreactor for adsorbing and degrading mixed antibiotics of sulfadimidine (SM2) and enrofloxacin (ENR) in aqueous solution under UV–Fenton conditions. The effects of different experimental conditions on the removal of antibiotics were investigated through L₉(4³) orthogonal experiments, and the synergistic effect and degradation mechanisms were systematically revealed. The results showed that the Fe₃O₄@C Fenton system demonstrated significantly enhanced catalytic activity, with hydroxyl radical (OH˙) concentrations of approximately 6.2 and 6.7 times higher than those observed in the Fe₃O₄ and Fe₃O₄ + AC Fenton systems, respectively. Moreover, the degradation pathway and mechanism analysis revealed that the adsorption and degradation behavior of the two mixed antibiotics in the Fe₃O₄@C Fenton system could be better described using pseudo-secondary kinetic models. The substantial improvement clearly indicates that the Fe₃O₄@C composite serves as a highly efficient microreactor for H₂O₂ decomposition in the Fenton process, thus providing a new avenue for the degradation of mixed antibiotics in water.