The hydrolysis reaction of ammonia borane (AB) is an efficient and effective way to produce hydrogen, but designing a highly efficient and structurally stable catalyst poses certain challenges. In this study, we proposed a low-temperature phosphidation method to synthesize cobalt phosphide catalysts (CoP-x), which possess adjustable morphology and catalytic activity, and are suitable for AB hydrolysis reactions. Among all samples, CoP-85 exhibited the best performance at 15 °C, achieving complete conversion of AB within 0.71 min, with a turnover frequency of 7.0 min−1 and an apparent activation energy of 74.29 kJ·mol−1. Isotope experiments using D2O revealed a significant kinetic isotope effect (KIE = 2.7 ± 0.2), indicating that the cleavage of the O-H bond in water participates in the rate-determining step. Structural analysis revealed that CoP-85 possesses a hollow flower-like structure with a high specific surface area, providing multiple active sites and facilitating mass transfer during the reaction. However, after ten consecutive cycles, the catalytic activity decreased significantly due to the loss of available active sites resulting from the collapse of the hollow structure. This work establishes the correlation between phosphidation-controlled morphology and catalytic performance, and provides insights into the design of cobalt phosphide catalysts for hydrogen generation.

Hydrogen energy as a renewable resource has drawn wide attention. However, the lack of efficient and durable catalysts for ammonia borane (AB) dehydrogenation hinders its practical application. In this work, CoCuP nanoparticles were anchored on Ti3C2 MXene nanosheets through a molten-salt-assisted strategy and subsequent phosphidation. The optimized CoP2-Cu3P/Ti3C2 catalyst integrates Co-Cu bimetallic synergy, phosphorus–induced electronic modulation, and metal-support interactions, thereby enabling efficient interfacial charge transfer and abundant accessible active sites. As a result, CoP2-Cu3P/Ti3C2 delivers rapid hydrogen generation from ammonia borane hydrolysis under visible light, with complete H2 release within 0.68 min at 298 K, a turnover frequency of 1168.8 h−1, and an apparent activation energy of 42.46 kJ mol−1. These findings highlight CoCuP/Ti3C2 interface engineering as a viable strategy for constructing low-cost and high-performance catalysts for chemical hydrogen storage.

This review presents the first systematic analysis of supramolecular organization in halonium-based systems driven by halogen bonding (XB) interactions. Through comprehensive examination of approximately 600 crystal structures from the Cambridge Structural Database, we establish major principles governing XB-directed assembly patterns across diverse halonium species. Monocationic halonium salts paired with monoanionic counterions constitute over 50% of characterized structures, predominantly forming 0D (85%) and 1D (15%) assemblies. Heterotetrameric motifs—cyclic assemblies comprising two cations and two anions connected through four intermolecular XBs—emerge as the dominant organizational principle (58% of structures). Critically, anion geometry plays the decisive role in directing supramolecular architecture, while cation structure exerts minimal influence. Iodonium (91%) and bromonium derivatives follow consistent assembly trends favoring heterotetrameric motifs, whereas chloronium salts exhibit anomalous behavior. Polycharged systems generate more complex 1D and 2D networks through linking of basic heterotetrameric units. Zwitterionic halonium compounds utilize analogous dimeric motifs as building blocks for extended 1D, 2D, and 3D assemblies, demonstrating promise as building blocks for noncovalent organic frameworks. These findings establish halonium salts as reliable platforms for predictable XB-based crystal engineering.

Abstract This work presents the first systematic study of halogen bonding interactions between iodine(III) centers of diaryliodonium cations and selenocyanate (SeCN–) anions─a previously undocumented type of IIII···Se contact. A series of diaryliodonium selenocyanates was synthesized via anion metathesis and characterized by single-crystal X-ray diffraction; DFT calculations were employed to analyze the nature of noncovalent interactions. Crystallographic analysis revealed short I···Se (3.22–3.30 Å, Nc 0.83-0.85) and I···N (2.82–2.96 Å, Nc 0.80-0.84) contacts forming heterotetrameric and heterooctameric assemblies. Comparison with the structurally analogous thiocyanate systems uncovered a remarkable architectural switch: while iodonium thiocyanates preferentially form 4-atomic cycles via I···N interactions, the selenocyanate analogues adopt 8-atomic heterotetrameric arrangements involving I···Se contacts. Computational analysis demonstrates that this switch is driven by the enhanced covalent character of IIII···Se versus IIII···S halogen bonds, as evidenced by larger Wiberg bond indices (0.16–0.20 vs 0.13–0.16 for I···S). The larger covalent contribution and charge transfer capability in I···Se bonds (BSSE energies −21 to −25 kcal/mol vs ∼ – 13 kcal/mol for the I···N interaction in the same selenocyanate systems) create a stronger energetic preference for I···Se bonding compared to the more balanced competition between I···S and I···N in thiocyanates. These findings establish chalcogen selection as a tool for tuning supramolecular architectures, identify SeCN– as an effective halogen bond acceptor, and expand the library of Se-based acceptors available for iodine(III) sites.

A method for the preparation of polyfluorinated diaryldisulfanes using 65

Single-atom catalysts (SACs) are assumed to remain structurally static during catalysis, while dynamic behavior under operating conditions is rarely explored. We propose a Structure-Mobility-Activity-Restructuring-Thermodynamics (SMART) framework to replace the static structure-activity framework, establishing atomic mobility as a critical parameter. In this work, under identical conditions, we conduct a comprehensive comparison of the behavior of SACs based on Ni, Pd and Pt in the hydrogen evolution reaction (HER), expanding the fundamental knowledge about the dynamic behavior of heterogeneous systems. Here, we show that Pt, Pd, and Ni atoms on graphite do not remain isolated during HER but migrate and thermodynamically self-assemble into nanoclusters. Using identical-location SEM, HAADF-STEM, XPS, electrochemical analysis, DFT modeling, and machine learning analysis, we demonstrate that catalytic behavior is governed not only by initial atomic dispersion, but by metal-specific atomic mobility. Pd atoms exhibit rapid migration with the lowest Tafel slope (37 mV dec-1), Pt shows intermediate mobility and performance (53 mV dec-1), while Ni remains dispersed longest but is less active (76 mV dec-1). DFT reveals that diffusion barriers correlate with cohesive and binding energies, providing a quantitative explanation for the observed restructuring trends.

This work presents a novel cooperative supramolecular engineering strategy based on the simultaneous utilization of halogen bonding (IN) and hydrogen bonding (HN) interactions for the directed self-assembly of three structurally distinct nitronyl nitroxide radicals: 2-(4-iodophenyl)-4,4,5,5-tetramethylimidazolin-1-oxyl-3-oxide (1), 2-(4-iodoethynylphenyl)-4,4,5,5-tetramethylimidazolin-1-oxyl-3-oxide (2), and 2-(2,3,5,6-tetrafluoro-4-iodophenyl)-4,4,5,5-tetramethylimidazolin-1-oxyl-3-oxide (3) with 1,4-diazabicyclo[2.2.2]octane (DABCO). We synthesized and characterized cocrystals (1-3)DABCO containing these iodine-substituted nitronyl nitroxide radicals with varied electronic properties. The primary novelty lies in demonstrating that cooperative dual-mode noncovalent assembly significantly outperforms single-interaction approaches, achieving quantitative enhancement of magnetic exchange interactions by nearly two orders of magnitude from approximately 0 K for unassociated radicals to -78 K for supramolecular assemblies. The 3DABCO system approaches the literature benchmark for purely organic nitronyl nitroxide materials, representing a substantial advancement in metal-free magnetic coupling strength. Comprehensive theoretical analysis using DFT, energy decomposition analysis, natural bond orbital analysis, and quantum theory of atoms in molecules elucidated the mechanistic basis for cooperative enhancement, revealing orthogonal energetic profiles where halogen bonds exhibit predominantly electrostatic character with significant orbital contributions, while hydrogen bonds show dispersive dominance with minimal orbital involvement. This complementary nature enables additive stabilization without competitive interference between interaction modes. The methodology addresses inherent limitations of single-interaction approaches, providing enhanced predictability and tunability compared with serendipitous discoveries.

A transmetalation strategy has been developed to access sulfonamide-functionalized palladium(II) and platinum(II) dithiocarbamate complexes that are inaccessible through direct functionalization due to the kinetic inertness of these metals. While kinetically labile nickel(II) dithiocarbamates readily undergo sulfonamide insertion into NiII-S bonds, the corresponding PdII and PtII complexes are resistant to direct functionalization. To circumvent this limitation, NiII complexes bearing preinstalled sulfonamide modifications were employed as transmetalation precursors. Two families of chelate complexes were obtained: N,S,S,S-tetradentate complexes with one sulfonamide fragment and N,S,S,N-tetradentate complexes featuring two sulfonamide moieties. The procedure was scaled to gram quantities. The versatility of this methodology was demonstrated through the synthesis of ML(NSCN) (M = Pd, Pt) species containing cyclometalated N∧S or N∧C ligands (L). X-ray crystallographic analysis of 19 structures revealed characteristic inequivalent C-S bond lengths (averaging 1.76 Å vs 1.71 Å across all structures) and partial C-N double bond character, consistent with significant contributions from both dithiocarbamate and thioureide resonance structures. This work provides a general and scalable route to sulfonamide-functionalized Group 10 metal dithiocarbamate complexes that cannot be accessed by direct methods.

Plasmon-assisted catalysis offers an attractive route for solar-to-chemical energy conversion, yet its practical integration into scalable flow systems remains limited by complex fabrication steps and poor nanoparticle stability. Here, we report a one-step laser-assisted method for simultaneously forming gold nanoparticles (Au NPs) and patterning microchannels on metal-organic framework (MOF)-functionalized polyethylene terephthalate (PET) substrates derived from waste plastic. Using a 405 nm laser, the in situ reduction of HAuCl4 within a UiO-66 matrix deposited on PET enables homogeneous Au NPs formation (≈5.4 nm) and precise microchannel definition without the need for additional reagents or post-processing. The resulting PET@Au composites exhibit strong plasmon resonance at 550 nm and catalytic activity for the degradation of methylene blue under visible light, confirming their functional performance. This approach combines plasmonic functionality, low-cost materials, and sustainable processing into a scalable platform for the development of integrated microfluidic and photocatalytic devices.

Enzyme-induced cytotoxicity can be considered the main challenge in modern cancer therapy that provides unique opportunities for targeted apoptosis. To address this challenge, we implemented enzyme-triggered activation of alkoxyamine-galactose conjugates with the formation of active carbon-centered radical species for the apoptosis of cancer cells. The comparative analysis of two alkoxyamine derivatives, bearing stable and self-immolative linkers between the radical precursor and galactose moiety, revealed the crucial role of molecular structure in anticancer activity. The study of cytotoxicity and induced oxidative stress of free amine and two galactosides revealed the enzyme-dependent nature of the activity of alkoxyamines having a self-immolative linker against distinct cancer cell lines such as PC-3 (prostate adenocarcinoma), SKOV-3 (ovarian adenocarcinoma), MCF-7 (breast adenocarcinoma), A-431 (epidermoid carcinoma), and Jurkat cells (human T-lymphoblastic leukemia). The collected data prove the applicability of enzyme-triggered glycosylated alkoxyamines as a new family of targeted prodrugs against cancer.

In contrast to polymer-to-polymer recycling of waste polyethylene terephthalate (wPET), chemical upcycling into added-value molecules beyond terephthalic acid is a promising strategy.Among possible transformations, electrophilic substitution offers a direct path,...

The selective detection of chlorinated aromatic hydrocarbons (CAHs) in environmental samples is challenging due to matrix interference effects. We report a surface-enhanced Raman spectroscopy (SERS) sensor that combines mesoporous Au films with UiO-66-I metal-organic framework (MOF) coatings to achieve the selective detection of CAHs. We show that mesoporous Au films can be considered hyperuniform two-dimensional (2D) materials where long-range correlations and local disorder assist in electromagnetic hotspot formation for SERS. Infiltrating the mesoporous Au films with UiO-66-I serves dual functions critical to sensor performance: First, its iodine-functionalized linkers selectively recruit CAHs from complex matrices through halogen bonding (HaB), concentrating target molecules at SERS hotspots while excluding common interferents. Second, the high refractive index of the MOF enhances light coupling by limiting scattered light, concentrating optical energy on the adsorbed CAHs for SERS enhancement. At optimal MOF thickness, the sensor achieves a detection limit below 1 × 10-10 M for 1,4-dichlorobenzene and 4-chlorobiphenyl, surpassing environmental standards by several orders of magnitude. The sensor demonstrates excellent selectivity for CAHs over common interferents, including protein, polycyclic aromatic hydrocarbons, and complex environmental matrices. Furthermore, the sensor maintains performance through multiple adsorption-desorption cycles, enabling reuse. This approach combines reticular chemistry with self-assembled nanostructured metals to achieve both high sensitivity and selectivity in complex environmental samples.

Laser reduction of graphene oxide (GO) is a promising approach for achieving flexible, robust, and electrically conductive graphene/polymer composites. Resulting composite materials show significant technological potential for energy storage, sensing, and bioelectronics. However, in the case of insulating polymers, the properties of electrodes show severely limited performance. To overcome these challenges, we report on a post-processing redox treatment that allows the tuning of the electrochemical properties of laser-induced rGO/polymer composite electrodes. We show that the polymer substrate plays a crucial role in the electrochemical modulation of the composites’ properties, such as the electrode impedance, charge transfer resistance, and areal capacitance. The mechanism behind the reversible control of electrochemical properties of the rGO/polymer composites is the cleavage of polymer chains in the vicinity of rGO flakes during redox cycling, which exposes rGO active sites to interact with the electrolyte. Sequential redox cycling improves composite performance, allowing the development of devices such as electrolyte-gated transistors, which are widely used in chemical sensing applications. Our strategy enables the engineering of the electrochemical properties of rGO/polymer composites by post-treatment with dynamic switching, opening up new possibilities for flexible electronics and electrochemical applications having tunable properties.

Organic nitroxide radicals - specifically chloro-, bromo, and iodo-substituted nitronyl nitroxides - exhibit self-assembly in crystalline states through the combined action of halogen (Hal center dot center dot center dot ONO) and hydrogen (ONO & ctdot;HMe) bonds. Theoretical calculations reveal that halogen bonds primarily govern the association of these nitroxides. This halogen bonding facilitates the proximity of atoms carrying spin densities of opposite signs, thereby promoting ferromagnetic intermolecular exchange interactions. This research demonstrates, for the first time, that halogen bonding can establish channels facilitating ferromagnetic intermolecular exchange between paramagnetic centers in organic nitronyl nitroxide radicals. This breakthrough discovery expands the potential applications of halogen bonding in the supramolecular modulation of magnetic properties within high-spin clusters-a function that was previously attributed exclusively to hydrogen bonding.

Herein, we developed a new synthetic approach for the preparation of N-arylated 1,2,4-oxadiazin-5(6H)-ones by direct arylation with diaryliodonium salts. The reaction with symmetrical diaryliodonium salts using CuI as a catalyst proceeded in toluene in the presence of DIPEA at 60 °C with the formation of the desired products in isolated yields of 46 to 97% (20 examples). The use of more readily available unsymmetrical diaryliodonium salts required higher reaction temperatures (up to 100 °C) to achieve similar yields. The only limitation observed in reaction was with an ortho-substituted iodonium salt. In all other cases, the developed approach allowed the preparation of a broad range of N-arylated 1,2,4-oxadiazin-5(6H)-ones under mild conditions utilizing a cheap and readily available catalyst.

Imidazoles are considered the merit heterocyclic moiety in medicinal chemistry and drug design. Here, we report on a convenient method for the aerobic oxidation of imidazolines under mild conditions using the cheap and available CuSO4 center dot 5H(2)O as the catalyst. The proposed method allows one to prepare 2-arylimidazoles bearing electron-donating and -withdrawing groups in good and quantitative yields. The developed procedure is applicable for the preparation of labile and oxidation-intolerant heterocyclic moieties.

Two series of stable verdazyl radical derivatives, specifically 1,2,4,6-substituted-1,4-dihydro-1,2,4,5-tetrazin-3(2H)-ones (also called "alkylverdazyls" or "AlkVZs"), were systematically investigated in photoactivated C-N bond homolysis. In-depth evaluation of their mechanisms indicated that several factors played a pivotal role in the generation of radicals during photon absorbance. From quantum chemical calculations, it was found that the most influential factor is the generation of charge-separated excited states, where one electron is located at the verdazyl moiety and the second one is distributed at the alkyl part. The theoretical approach also allows one to predict the reaction rate constant based on the oscillator strengths of the S0 → S1 transition in AlkVZs. Surprisingly, the photon density of the LED source has a strong impact on controlling the reaction direction, and decreasing the light power could lower the yield of radicals by twofold with the full conversion of the starting materials in all cases. Our results delineate prospective approaches for achieving high yields in photochemical transformations via the variation of the wavelength of light, the careful design of the molecular structure and alterations in the LED power.

A novel approach for controlled mono- and double-insertion of sulfonamide fragments into Ni-S bonds of [Ni(S2CNR2)2] complexes has been developed using aryl and alkyl sulfonyl azides as sulfonamide sources. The reaction selectivity is governed by the choice of solvent (hexafluoro-2-propanol for the monoinsertion versus isopropanol for the double-insertion) and temperature (50 and 80 °C, respectively). This method provides convenient access to previously unreported monoinsertion products [NiL(S2CNR2)] along with the double-insertion complexes [NiL2] (L = NSO2(R')S2NR2) under mild conditions. The scope of the reaction was demonstrated using 18 sulfonyl azides and 6 nickel(II) dithiocarbamates, affording the target complexes (38 examples) isolated in 9-97% yields. The method's practicality was confirmed through gram-scale syntheses of three representative examples (72, 76, and 92%). X-ray diffraction analysis of 15 new complexes revealed that sulfonamide fragments occupy axial positions relative to the dithiocarbamate plane, with the modified C-S bonds showing inequivalent lengths (1.76-1.78 Å for C-SN vs ∼ 1.71 Å for C-SNi). Mechanistic studies uncovered that insertion products can undergo spontaneous disproportionation in solution.

Six aryl- and pyridine-substituted nitronyl-nitroxide radicals were synthesized and characterized to investigate their optical anisotropic properties. Single-crystal X-ray diffraction analysis revealed molecular packing organized by either halogen and hydrogen bonding or hydrogen bonding alone. Single-crystal electronic absorption spectra in the visible region of three studied radicals exhibit pronounced linear dichroism, while single crystals of other radicals do not demonstrate this property. Time-dependent DFT and ab initio calculations were employed to determine the transition dipole moment (TDM) vectors corresponding to the long-wavelength absorption bands. For all radicals, these vectors are found to be practically parallel to the O & ctdot;O direction of the nitronyl-nitroxide chromophore. Correlation between the dichroic properties and crystal structure was established through comprehensive analysis of TDM vector orientations relative to the crystal surface. The strongest dichroic effect was observed in crystals where all projections of the TDM vectors onto the illuminated face are parallel to each other, while weaker or absent effects correspond to non-parallel arrangements. This study constitutes the first systematic investigation of linear dichroism in paramagnetic organic crystals, thereby establishing new avenues for developing multifunctional materials that respond to both optical and magnetic stimuli.