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Electrolyte solutions are vital to energy storage devices, significantly influencing their capacity, safety, and cost efficiency. Lithium salts based on multidentate anions have shown remarkable potential in energy storage, particularly when dissolved in acetonitrile. These solutions exhibit exceptionally high ionic conductivities, even for concentrations above the standard 1 mol L⁻¹ solutions. To directly probe bulk solvent and solvation shell dynamics in lithium salt solutions, the ultrafast optical Kerr effect (OKE) method is utilized. We investigate the microscopic dynamics of LiTFSI (lithium bis (trifluoromethanesulfonyl) imide) solutions at various concentrations in acetonitrile. The measured data, combined with a global analysis method, reveal that the solvent remains highly dynamic and nearly bulk-like, even at high concentrations where a significantly reduced number of solvent molecules are available to solvate the cations in solution. These findings support recent explanations as to why acetonitrile-based electrolyte solutions exhibit higher conductivity compared to, for instance, other nonaqueous electrolyte solutions. In electrolytes based on acetonitrile, a greater proportion of free solvent molecules results in lower overall viscosity. An abundance of uncoordinated solvent molecules facilitates higher ion conduction, compared with the more limited ion mobility observed in other LiTFSI electrolyte systems.

A significant amount of abandoned plastics has caused serious harm to the environment and ecosystems. The urgent demand for carbon-neutral technology has driven the effective recycling of plastic waste. Various chemical approaches have been extensively explored for plastic waste management, with recycling strategies aimed at selectively producing high-value products garnering increasing attention. Notwithstanding considerable progress, each treatment method possesses certain constraints. Multi-step cascade coupling offers a viable strategy for efficient plastic recycling, affording enhanced selectivity towards desired products. This review provides a systematic review of the reaction mechanisms and representative studies of pyrolysis, photocatalysis and electrocatalysis for various types of plastics. A strategy centred on the design of specific intermediate molecules enables a polymer conversion pathway where depolymerisation into monomers, oligomers or other intermediates is followed by their selective transformation into high-value chemicals. Uniting established methods like thermal degradation and solvolysis with emerging fields—including photocatalysis, electrocatalysis and biotransformation—this review proposes a coherent framework for the rational design of multi-stage or cascade plastic recycling processes. This approach paves the way for the efficient transformation of abandoned plastics into valuable chemicals.

In this paper, we report the synthesis, structure, and application of bis-catecholaldimine-based Cu^II-Salen complex as a cathode material in lithium-ion battery. [Cu(LH₂)] (1) complex was prepared using the ligand 6,6′-{[Ethane-1,2-diylbis(azanylidene)]bis(methanylidene)}-bis(3,5-di-tert-butyl-1,2-dihydroxybenzene) (LH₄). The complex 1 was characterized structurally by single-crystal X-ray diffraction technique. It was also further characterized by various techniques such as high-resolution mass spectrometry, Fourier Transform Infrared, thermogravimetric analysis, and elemental carbon, hydrogen, nitrogen (CHN) analysis. Complex 1 is a mononuclear complex that crystallizes in the triclinic P-1 Space group with a Cu⁺² ion present in a slightly distorted square planar geometry. Complex 1 [Cu(LH₂)] was further employed as a cathode material for a secondary lithium-ion battery, which shows superior cyclic and rate capability performance. The [Cu(LH₂)] (1) electrode shows an average capacity of 73.5 mAh/g at 50 mA/g after rate capability test, as compared to the 21.8 mAh/g specific capacity for the LH₄ electrode. To understand the redox chemistry of the Cu-complex, a series of Density functional theory (DFT) computations were carried out for the complex 1 and its corresponding one- and two-electron reduced species.

Tetrathiafulvalene (TTF) is a well-known redox-active molecule that undergoes two reversible one-electron oxidations to afford stable cationic species. Its redox and optical properties, as well as molecular geometry and self-association behavior, can be systematically tuned through incorporation of a π-conjugated framework between the two dithiole rings. Herein, we report the synthesis of novel extended TTF scaffolds in which two fluorene-dithiafulvene units are rigidly connected via a 2,2′-biphenyl spacer. Crystallographic, computational, and ¹H nuclear magnetic resonance (NMR) spectroscopic studies show that the neutral scaffolds take a conformation allowing for intramolecular associations between the two fluorene-dithiafulvene units. Electrochemical studies further reveal intramolecular stabilization of radical cations owing to mixed valence dimer formation, supported by a strong near-infrared absorption.

This review provides a concise overview of the trinitromethyl/gem-dinitromethyl functionalized energetic compounds reported over the past decade, focusing on molecular design, synthetic routes, and performance evaluation. The skeletons of these energetic molecules primarily include monocyclic, fused heterocyclic, linked heterocyclic, bridged heterocyclic systems, and ionic salts. As the aspect of synthesis, the predominant strategy for introducing polynitromethyl groups such as trinitromethyl and gem-dinitromethyl remains the nitration of precursor groups, including cyano, ethyl acetate, and acetone moieties on the molecular backbone. However, the implementation of molecular skeleton editing techniques for concurrent construction of cyclic frameworks and incorporation of gem-dinitro energetic groups has experimentally verified that this methodology facilitates more secure and efficient integration of energetic functionalities with molecular skeletons. To address the challenge of balancing safety and energy density in high-energy-density materials, current approaches rely heavily on constructing extensively conjugated molecular frameworks functionalized with trinitromethyl or gem-dinitromethyl. Analysis of reported energetic compounds from the perspectives of molecular design and structure-performance relationships indicates that rational integration of trinitromethyl/gem-dinitromethyl groups with conjugated fused or linked heterocyclic skeletons, along with further expansion of planar conjugated structures, represents an effective strategy for designing novel energetic compounds that simultaneously exhibit high energy content and stability.

The effect of CuSO₄ on the stability of an immobilized laccase during the oxidation of HMF to FFCA was determined in a batch bioreactor and in a triphasic flow bioreactor. The enzyme was immobilized on a support functionalized with an epoxide and glyoxyl group; the latter achieved the highest immobilization yield by activity (87.5%). In batch oxidation of HMF catalyzed by laccase immobilized on a support with glyoxyl groups reached the highest conversion percentages (100%). In the biocatalyst stability, the addition of 20 mM CuSO₄ allowed achieving 50% HMF conversion at the end of the third cycle. In the absence of CuSO₄, the biocatalyst was unable to catalyze the reaction. The oxidation in packed-bed flow bioreactor resulted in the production of FFCA only. With CuSO₄, the stability of the biocatalyst was maintained for 48 h, with a FFCA yield of 95%. The UM values (0.2–5 cm/min) demonstrated that above an air flow rate of 0.1 mL/min, there are no mass transfer problems affecting the reaction yield. The space-time yield of FFCA (STY FFCA) (1.54 (mM/min)) was higher for the continuous system in the presence of CuSO₄. Overall, this system provides a promising and scalable platform for sustainable industrial biocatalysis.

Awareness of new potential doping agents and the proactive implementation of detection methods are key aspects of preventive antidoping research. Ryanodine receptor-1-calstabin complex stabilizers (RYR-stabilizers) are a novel class of drug candidates for the treatment of various diseases associated with leaky Ca²⁺ channels in the cardiac or skeletal muscle. Also, intense physical activity was shown to transiently cause leakage of skeletal muscle Ca²⁺ channels, and RYR-stabilizers have been shown to restore normal activity and, thus, increase endurance performance. Consequently, such compounds are relevant targets in doping controls, and to date, in particular, compounds S107, JTV-519, ARM 036, and ARM 210 have been subject of antidoping research. In this study, ARM 036 and ARM 210 as well as the commercially available compounds S107 and JTV-519 were synthesized using a multistep approach. Subsequently, all compounds were investigated concerning their in vitro metabolic behavior, and various metabolites were identified. Selected metabolites were then chemically synthesized for comprehensive structure confirmation. The findings of this study will contribute to routine doping control analytical programs and allow for improving existing detection methods.

The shift from fossil-based to biobased feedstocks is paramount for sustainable chemical production. This work presents an efficient, catalyst-free method for synthesizing a diol-rich polyol from epoxidized castor oil. Unlike conventional acid-catalyzed methods, the presented approach minimizes undesirable side reactions, yielding a polyol with a high hydroxyl number of 6.5 per triglyceride (370 mg KOH/g) and a low oligomer content. By performing the reaction at 130°C in an overheated water–dioxane mixture, we achieved full epoxide conversion in 24 h, making the process competitive with acid-catalyzed systems. This resulting polyol, characterized by a high content of adjacent diols, was utilized to prepare novel, recyclable polyboronates with 1,4-phenylenediboronic acid. Based on NMR analysis, the stoichiometry of the reaction between the synthesized polyol and phenylboronic acid was determined. Additionally, a regioselective preference for the formation of six-membered cyclic esters with 9,10,12-trihydroxyoctadecanoates, which constitute the main fraction in the synthesized polyol, was revealed. The polymers exhibit properties of low-cross-linking-density elastomers. The dynamic covalent nature of the boronate linkages was confirmed through DMTA and stress relaxation experiments. This research establishes hydroxylated castor oil as a robust and sustainable building block for polymer materials.

Naturally occurring chromanols, such as α-tocopherol (vitamin E), exhibit diverse biological activities. Their structural complexity, arising from the conformationally labile dihydropyran ring, has prompted extensive research into their conformational behavior. α-Tocopherol O-glycosides are promising vitamin E prodrug candidates, driving research on their synthesis and molecular dynamics (MD). In this work, four chromanyl glucosides were studied. Using crystallography, dynamic nuclear magnetic resonance (DNMR), solid-state NMR (ssNMR), and computational modeling (MD simulations, CASTEP), the conformational effects induced by sugar residues at the C6 position of a vitamin E model compound (2,2,5,7,8-pentamethylchroman-6-ol) in α- and β-orientations were investigated. Despite structural similarities, significant solid-state differences were observed, particularly between the anomers of peracetylated derivative 4, where the α-anomer displayed molecular disorder absent in the β-isomer - suggesting the presence of multiple conformational states in the crystal lattice. Density functional theory calculations confirmed insignificant energy differences (<0.5 kcal/mol) among the four optimized structures of chromanyl 2,3,4,6-tetra-O-acetyl-α-D-glucopyranoside (4α), implying that the coexisting configurations are stabilized by entropy. Gauge-including projector-augmented wave NMR calculations enabled precise ssNMR peak assignments, while MD simulations indicated static crystalline disorder in 4α. This integrated approach provided a detailed structural insight into chromanyl glucosides, advancing understanding of their conformational behavior.

Covalent organic frameworks (COFs), characterized by their tunable porosity and abundance of functional moieties, offer an exceptional scaffold for the uniform dispersion and stable immobilization of metal species. Herein, we report the efficient immobilization of highly dispersed Fe(III) ions into a porphyrin-functionalized COF (AP-COF), synthesized via Schiff-base condensation between 4,4′-(ethyne-1,2-diyl)dibenzaldehyde and 5,10,15,20-tetrakis(4-aminophenyl)-21H, 23H-porphyrin. The resulting Fe@AP-COF was characterized by various techniques. High-resolution transmission electron microscopy and dark field imaging confirmed the homogeneous distribution of Fe(III) ions within the COF matrix. The Fe@AP-COF demonstrated excellent thermal robustness and high surface area, which facilitated the effective anchoring of active iron centers. This catalyst exhibited remarkable performance in promoting the one-pot synthesis of dihydropyrimidinones (DHPMs) via Biginelli multicomponent reaction under optimum conditions. Furthermore, the Fe@AP-COF showed outstanding structural integrity, minimal Fe leaching, and excellent recyclability over multiple catalytic cycles. Comparative analysis revealed its superior catalytic activity to both homogeneous and conventional heterogeneous Fe-based catalysts. These insights highlight the valuable prospects of metal-functionalized porphyrin-based COFs as adaptable and efficient platforms for advanced catalytic applications.