A ruthenium-catalyzed addition of sulfonic acids to acetylene is reported. This method employs bulk industrial feedstock acetylene as C2 synthon under atmospheric pressure to access vinyl sulfonates in good to excellent yields without using toxic mercury catalysts, offering high atom economy and practical scalability. The resulting vinyl sulfonates serve as versatile vinylating reagents and can be readily transformed into diverse functionalized molecules.

Single-atom catalysts (SACs), represented by Fe─N─C, are promising alternatives to Pt in proton exchange membrane fuel cells (PEMFCs). However, the molecular-scale misalignment of the SACs at the triple-phase interfaces (TPIs) has led to extremely low atomic efficiency, making it difficult to translate the high activity of SACs into the actual cell performance. Therefore, the design of the catalyst layer structure to increase the density of reactant-accessible single sites is crucial for the application of SACs in PEMFCs. Here, we report tailored catalyst layer structure induced by hierarchical porous Fe─N─Cpot catalysts with tuned surface hydrophilicity. Coarse-grained molecular dynamic (MD) reveals macropores and tuned surface hydrophilicity act as molecular-level "on-switches" that pull Nafion/water domains deep inside, collapsing the classic transport bottlenecks for both O2 and H3O+. Combinatory spectroscopic evidence confirms the superiority of the structure in forming continuous mass transfer channels, thereby increasing site utilization of Fe by 80%. Exceptional Pmax at 1581mW cm-2 is achieved, and capable of sustaining 60k AST with 63% performance retained. This study establishes the first design rule that links pore hierarchy and surface chemistry to TPI activation.

Formaldehyde‑free phosphamide flame retardant with high atom economy for cotton based on p-π conjugation

Herein, we report a ball milling technique for the regioselective hydrophosphinylation of acrylamides and enamides, utilizing readily available Ph2PCl as the phosphine source and H2O as an additive under metal-free and toxic solvent-free conditions. Michael-type and Markovnikov hydrophosphinylation reactions have been achieved for acrylamides and enamides, respectively. The reaction features broad substrate scope, sustainable conditions and high atom economy, facilitating the rapid assembly of structurally diverse amide-based phosphine oxides in useful to good yields.

The interdisciplinary integration of conventional organic synthesis with advanced electrochemical methodologies has catalyzed the emergence of a transformative discipline: organic electrochemical synthesis. This innovative field has emerged as a pivotal player in addressing contemporary challenges of escalating energy scarcity and environmental degradation. This review initiates its discourse by examining cathodic reduction processes in organic-electrochemical synthesis systems. We systematically elucidate the electrochemically driven reduction-hydrogenation (deuteration) and reductive coupling reactions occurring at unsaturated bonds (CO, CN, and NN) through a critical analysis of recent advancements. Our comprehensive presentation aims to provide scholars with profound insights into the distinct advantages and underlying mechanisms that differentiate electrochemical organic synthesis from traditional catalytic approaches, particularly emphasizing its enhanced atom economy, superior energy efficiency, and improved environmental compatibility.

The development of operationally simple and environmentally benign synthetic strategies for constructing phosphorus-substituted heterocycles is highly valuable in organophosphorus chemistry. Herein, we report a straightforward and green radical cascade cyclization of diphenylphosphine oxide with isocyanides or heteroarenes for the synthesis of phosphorylated heteroarenes with high atom economy. With air as a green oxidant and ethanol as the solvent, without additional oxidants or bases, this one-pot protocol exemplifies the principles of green chemistry, enabling the construction of C-P and C-C bonds using an inexpensive, commercially available and low-toxicity catalyst. Studies on electron paramagnetic resonance and control experiments indicated that manganese(III) salt and O2 act in concert to achieve radical cascade cyclization, with superoxide radical anion (O2•-) contributing to this reaction.

Elemental sulfur (S8), an abundant petroleum byproduct, is leveraged as a linchpin monomer in an organobase-catalyzed step-growth addition polymerization with dithiols and diacrylates at ambient temperature. This method enables the scalable synthesis of poly(ester disulfide)s-featuring alternating ester and disulfide linkages-with exceptional atom economy ( > 95% yield), Mn up to 42.0 kDa, and dual functionality: biodegradable ester units and stimuli-responsive disulfides. Mechanistic studies reveal a chemoselective three-component coupling involving S8 ring-opening, disulfide anion formation, and Michael addition, quantitatively generating symmetric and asymmetric disulfides in near-equimolar ratios. Thermal and mechanical characterizations of the poly(ester disulfide)s reveal programmable properties: High thermal stability (Td,5% = 248-281 °C), tunable phase behavior (amorphous Tg = -64 °C to semicrystalline Tm = 142 °C), and reductive degradation. By overcoming traditional limitations of harsh conditions and monomer scope, this strategy establishes S8 as a versatile feedstock for functional polymers, opening avenues for dynamic materials in biomedicine and environmental remediation.

Single-atom sites (SASs) and their electrocatalysts offer outstanding catalytic activity and metal efficiency. Metal-organic frameworks (MOFs), with their tunable and multifunctional architectures, serve as ideal precursors for SASs, enabling atomic-level dispersion. However, current research often overlooks critical ambiguities in SAS definitions, intrinsic limitations, and characterization reliability. Moreover, prevalent destructive treatments, such as pyrolysis or sulfidation, inevitably compromise framework integrity, raising concerns regarding the trade-off between structural designability and conductivity. Accordingly, this Mini-Review critically revisits MOF-derived SASs by scrutinizing synthesis limitations and emphasizing the quantitative assessment of atomic utilization efficiency. Representative examples of emerging framework-retaining strategies, including ligand and defect engineering, are discussed to illustrate opportunities for preserving MOF advantages. Finally, future directions are proposed, focusing on dynamic structural reconstruction and operando validation to simultaneously enhance activity, stability, and scalability for practical energy conversion applications.

Under ball-milling, continuous mechanical energy enables a TEMPO-mediated single-electron process, while inexpensive ferric nitrate serves as the nitrogen source for in situ diazotization. This method rapidly converts anilines into aryl halides with broad functional-group tolerance, avoiding hazardous diazonium salts, external heating, and bulk solvents. The approach improves operational simplicity, atom economy, and sustainability, highlighting the power of mechanochemistry to promote redox-driven transformations and providing a practical alternative to conventional solution-phase halogenation.

An iridium(III) complex bearing a picolinamidato ligand has been developed as an efficient catalyst for the regioselective C3 alkylation of indoles and oxindoles via a borrowing hydrogen (BH) or hydrogen autotransfer strategy. A broad range of aromatic, heteroaromatic, and aliphatic alcohols, including diols, are successfully employed under solvent-free (neat) conditions with low catalyst loading, demonstrating excellent functional group tolerance. Significantly, this protocol combines high regioselectivity, atom economy, and operational simplicity by avoiding preactivated alkylating agents, external oxidants, or reductants, thereby advancing sustainable C-C bond-forming methodologies. The method is scalable and provides straightforward access to structurally diverse and biologically relevant indole and oxindole frameworks, which are prevalent motifs in pharmaceuticals and natural products. Control experiments, deuterium labeling studies, and spectroscopic investigations support a classical borrowing hydrogen mechanism involving Ir-hydride intermediates.

A practical and efficient regio- and stereoselective hydrophosphorylation of propiolates, as well as a multicomponent reaction incorporating an aldehyde component, is reported. Both processes proceed with atom economy in very straightforward experimental procedures. The reactions are catalyzed by DABCO (1,4-diazabicyclo[2.2.2]octane) and use readily available H-phosphonates as the phosphorylating agent.

We herein disclose a palladium-catalyzed asymmetric desymmetric cycloisomerization of alkynyl-tethered cyclohexadienes, providing optically pure hydrindanes with one tertiary and one quaternary stereocenter. This reaction features a broad substrate scope, high atom economy, and good to excellent enantioselectivities. In addition, the diene and enone motifs embedded in the products offer synthetic handles for further structural diversification.

Nanozymes are enzyme-mimicking nanomaterials that are promising for diverse biomedical applications; they enable stable, tunable, and multifunctional cancer therapies via exploiting tumor microenvironment (TME) cues to regulate reactive oxygen species (ROS) and catalytic activities locally, aided by state-of-the-art fabrication methods and artificial intelligence (AI)-assisted designs. This review summarizes recent developments in nanozyme-based cancer therapy, focusing on the underlying catalytic mechanisms, material classifications, and their multimodality integration for cancer treatment. It further examines oxidase (OXD), peroxidase (POD), catalase (CAT), and superoxide dismutase (SOD)-like nanozymes in chemodynamic (CDT), photothermal (PTT), photodynamic (PDT), sonodynamic (SDT), immune and starvation therapies (ST), emphasizing single-atom, multimetallic, biomimetic, and AI-assisted design strategies of nanozymes. Single-atom and multimetallic nanozymes offer superior catalytic precision, atom efficiency, and programmable pathways over conventional nanomaterials. While AI-assisted design accelerates discovery of optimal compositions and therapeutic environment compatibility, enabling controlled ROS generation and TME responsiveness and hence enhancing tumor selectivity and therapeutic efficacy, their combination may represent a transformative direction for precision cancer therapy. Despite encouraging progress, challenges related to in vivo specificity, long-term biosafety, scalable synthesis, and clinical translation remain. Addressing these issues through interdisciplinary innovation will be critical for advancing next-generation intelligent nanozyme platforms toward clinical oncology.

This paper presents an efficient strategy for constructing unsymmetric azobenzenes through a cascade reaction between arylamines and N-nitrosoaromatics. This process proceeds via initial N═N bond formation, followed by N-N bond cleavage and concomitant C-N bond formation. The method employs stable and readily available arylamines and N-nitrosoaromatics as starting materials, producing water as the sole byproduct. Additional advantages include mild reaction conditions, high atom economy, operational simplicity, and broad substrate scope with excellent functional group tolerance.

Axially chiral biaryl phosphines and their oxides are indispensable ligands in asymmetric catalysis, enabling diverse enantioselective transformations. Here, we report the design, synthesis, and applications of a new family of axially chiral phenanthryl-aryl phosphine ligands. We disclose a nickel-catalyzed atroposelective [4+2] cycloaddition of biphenylenes with 1-arylalkynes to give axially chiral phenanthryl-aryl bis- and monophosphine oxides, including 2,2'-bis(diphenylphosphine oxide)-1,1'-binaphthy (BINAPO) analogues, as well as monophosphine oxides (MOPOs) and 1-(2-diphenylphosphinyl-1-naphthyl)isoquinoline (QUINAPO) analogues, in high yields and with excellent enantioselectivity. The transformation features 100% atom economy, employs a nonprecious metal, shows broad substrate scope, scales well, and allows easy purification, underscoring strong practical utility. The oxides were readily reduced to the corresponding phenanthryl-aryl MOP- and BINAP-type P(III) ligands. Across multiple representative enantioselective transformations, including hydrogenation, arylation, allylation, and hydrosilylation, these new ligands consistently surpassed benchmark ligands, affording markedly higher enantioselectivity. Density functional theory (DFT) calculations indicate that the cycloaddition-generated phenanthryl unit deepens the chiral pocket around phosphorus, thereby accounting for the high level of stereocontro.

Catalytically converting 5-hydroxymethylfurfural (HMF) to 2,5-furandicarboxylic acid (FDCA) underpins renewable, bio -based plastics, yet designing metal-efficient catalysts remains challenging. Here, we combine alloy and support effects by anchoring AuPd alloy nanoparticles on 2D covalent organic frameworks (COFs). Rationalizing alloy composition and COF functionality yielded Au67Pd33/TTATP, which converted HMF → FDCA in water using atmospheric O2 mild conditions, delivering >99% FDCA yield, stable reusability, a turnover number (TON) of ∼100 at HMF/metal = 100, increasing to 518 at 600 (86.4% yield). High performance stems from alloy-support synergy that (i) partitions function (Au: HMF dehydrogenation; Pd: O2 activation) and (ii) matches adsorption-desorption (TTATP enriches HMF yet releases FDCA; alloy surfaces moderate HMF binding and avoid the strong FDCA adsorption of Pd alone), thereby enhancing metal atom efficiency.

ABSTRACT Electron donor–acceptor complexes provide a useful platform for photocatalyst‐free radical generation under visible light irradiation and has emerged as a sustainable strategy for synthetic applications. Previous synthetic strategies based on EDA‐complex formations are typically based on engineering leaving groups into the substrates to suppress back electron transfer that impedes forward reaction. However, such pre‐functionalization affects efficiency and atom economy. This review highlights recent developments in the use of strategies for EDA‐complex formations to induce photochemical coupling‐ and cyclization reactions that do not rely on preinstalled sacrificial leaving‐groups. Most examples rely on alternative strategies to circumvent back electron transfer such as bond cleavage, oxygen‐mediated oxidation, or excitation of EDA complex precursors. These studies illustrate the rising promise of EDA complexes without incorporation of sacrificial leaving‐groups and highlight their potential as a broadly applicable, atom‐economical platform for photocatalyst‐free radical transformations in modern organic synthesis.

Photocatalytic nonoxidative methyl activation and subsequent C─C coupling in the methyl group of arenes offer an attractive strategy for the coproduction of value-added polycyclic aromatics and hydrogen with 100% atom economy and positive delta Gibbs free energy. However, its application remains constrained by the limited availability of highly active redox sites capable of simultaneously facilitating efficient dehydrogenation oxidation and proton reduction. Herein, a platinum-silver dual-atom catalyst (PtAg DAC) anchored on CdS is designed to enable a water-assisted photocatalytic nonoxidative conversion of toluene to 1,2-diphenylethane with hydrogen evolution. In situ infrared, ESR, and DFT analyses unveil an atomic-scale synergy within the PtAg-Sbridge unit that facilitates C(sp3)-H cleavage of methyl and formation of key C7H7· radical via a water-assisted pathway, lowering the overall energy barrier from 3.02 to 1.31eV. Consequently, the PtAg DAC yields 1,2-diphenylethane at 32.8µmol g-1 h-1 with 77.35% selectivity, outperforming monometallic counterparts by up to 3.1-fold. Simultaneously, a hydrogen evolution rate of 89.8µmol g-1 h-1 was achieved over PtAg DAC, which was 2.1- and 6.5-fold higher than Pt and Ag single-atom catalysts, respectively, resulting in a solar-to-chemical energy conversion due to positive ΔG.

This study presents a novel, sustainable catalytic system for the Biginelli reaction, utilizing a sulfonated carbon catalyst synthesized from underutilized corn cob waste via ZnCl2 activation and dual step sulfonation. The resulting catalyst, 2S2Zn-500, exhibited high surface area (739m2/g), good acidity (0.48mmol/g SO3H), and well-defined mesoporosity, enabling efficient multicomponent synthesis of dihydropyrimidinones (DHPMs) under mild conditions (95°C, 5h) in biodegradable palm oil, a green solvent alternative. This catalyst delivered high yields up to 91% and demonstrated good reusability over five cycles with minimal loss in activity. Comprehensive characterization (XRD, FTIR, SEM-EDS, XPS, Raman, TEM, BET, TGA) confirmed its structural integrity, functional group incorporation, and thermal stability. The system achieved impressive green metrics (Atom Economy: 86-93%; E-factor: 21-32; PMI: 22-33), outperforming several literature-reported biomass-derived catalysts in terms of sustainability, efficiency, and operational simplicity. This is the first report of a ZnCl2-activated, sulfonated corn cob catalyst used in tandem with palm oil for Biginelli synthesis, offering a cost-effective, metal-free, and circular approach to biomass valorization. The integration of a renewable feedstock, recyclable catalyst, and eco-friendly solvent positions this work as a compelling model for green multicomponent synthesis and bio-waste utilization.

Atomic layer deposition (ALD), as a novel metal-loading approach, allows the customization of interesting metal active sites or precise control of the surface chemistry. The diffusion limitation of pore structures prevents the efficient deposition of relatively large organometallic precursors on medium/small-pore zeolites. A rich variety of etching strategies are proposed to facilitate deep deposition of reactive precursors. The Cu-ZSM-5(Na2CO3) catalyst showed a 2.3-fold enhancement in Cu loading compared with parent zeolite and more copper active sites at the same Cu-ALD cycles. The Cu-ZSM-5(Na2CO3) achieved the most excellent low-temperature deNOx performance and was accompanied by a wide temperature window, announcing the compatibility of medium-pore zeolite with the ALD technique. It was found that the diffusion of pore structures is the key to the coupling of ALD with zeolites when Si/Al is lower than 20, and the insufficient framework Al (FAL) is fatal for copper(II) hexafluoroacetylacetonate [Cu(hfac)2] deposition when Si/Al is higher than 20. Density functional theory (DFT) calculations verified that Cu(hfac)2 prefers to be deposited on FAL sites at the intersectional channels and the extra-framework Al is detrimental to copper deposition. DFT simulation also confirmed that the [Cu(OH)]+ ions have the lowest energy barrier in the rate-controlling step of redox pathways.