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A convenient phosphine-free strategy for synthesizing N-substituted carbazoles via "C-H" activation using a novel pyrazolyl-1,2,3-triazolyl Pd(II) complex is described. Dual "C-N" bond formation from 2-iodobiphenyls and amines affords carbazoles in good yields. Notably, benzenesulfonamides and aliphatic amines act as coupling partners, a transformation that has not been reported previously. The complex was confirmed by single-crystal X-ray diffraction.

We report a Pd(0)-catalyzed cascade that enables the stereoselective synthesis of syn-1,4-dicarbinol dihydronaphthalene esters through regioterminal-selective acetate walking and tandem cycloaddition. The transformation proceeds via a palladium-catalyzed allylic transposition that generates a reactive diene intermediate in situ, which undergoes a rapid intramolecular [4+2] cycloaddition under mild conditions. Notably, the cascade incorporates a diastereoselective, acid-mediated ring deletion step coupled with orthogonal esterification, yielding highly functionalized syn-dihydronaphthalenes as a single diastereomer. This work establishes a unified catalytic platform that merges organometallic reactivity with cycloaddition chemistry, providing a concise and versatile entry into dihydronaphthalene architectures.

[FeFe]-hydrogenases are highly efficient enzymes in the reversible catalysis of molecular hydrogen production and oxidation. Their active site, the H-cluster, consists of a [4Fe-4S]H subcluster linked to a binuclear [2Fe]H organometallic unit. Many [FeFe]-hydrogenases, such as the one from Desulfovibrio desulfuricans (DdHydAB), possess accessory Fe-S clusters (F and F') that mediate electron transfer. This study employs hybrid quantum mechanics/molecular mechanics (QM/MM) methods to characterize the electronic structure and thermodynamic landscape associated with redox and protonation events in the complete Fe-S cluster network of DdHydAB. Our calculations indicate that the F' cluster plays a key role in the initial reduction of the oxidized resting state, acting as the preferential site for the accumulation of the first electron. Analysis of protonated states, upon reduction events, reveals a strong correlation between protonation and electron transfer (PCET), with protonation at the H-cluster inducing electron transfer from the F' cluster to the H-cluster. Calculations indicate that the formation of a terminal hydride is energetically favored over ADT protonation, and subsequent isomerization to a bridging hydride (μ-H) is further stabilizing, albeit potentially kinetically limiting. The study highlights how accessory clusters influence the electronic distribution and redox properties of the H-cluster, underscoring the importance of considering the entire Fe-S cluster system for a complete understanding of the catalytic mechanism of [FeFe]-hydrogenases.

We report the highly enantioselective nucleophilic addition reaction of simple ketone-derived hydrazones. Accordingly, a ErCl₃-catalyzed cyanation of both aliphatic and aryl ketone hydrazones is achieved for the facile access of Cα-tetrasubstituted α-hydrazino nitriles in up to 96% ee, by using the sterically confined pyridinebisoxazoline (PYBOX) ligand featuring a sulfonyl group at the pyridine C4 position. This method enables the shortest catalytic enantioselective total synthesis of L-carbidopa, a drug that could treat the symptoms of Parkinson's disease, with 82% overall yield in four steps. These adducts are valuable synthons to various α-tertiary hydrazines and related azacycles that are interesting targets for medicinal studies and pesticide research. From our biological analysis, a chiral α-hydrazino nitrile with good insecticidal activity against Aphis gossypii (LC50 = 15.11 mg∙L-1) was identified, rivaling commercial insecticides.

This work presents the design, synthesis, and catalytic evaluation of a novel heterogeneous organometallic catalyst, fabricated through the immobilization of a palladium-Schiff base complex onto the amino-functionalized titanium-based metal-organic framework, NH2-MIL-125. The resulting composite material was thoroughly characterized using a suite of analytical techniques, including FT-IR, XRD, FE-SEM, TGA, ICP-OES, EDS, and BET surface area analysis, confirming the successful modification and preservation of the MOF architecture. The catalyst demonstrated exceptional performance in facilitating asymmetric Suzuki-Miyaura cross-coupling reactions, proving to be both highly active and stereoselective. The enantiomeric excess (e.e.) of the produced axially chiral biaryls was quantified via high-performance liquid chromatography (HPLC) employing chiral stationary phases. Remarkably, the catalyst afforded biaryl derivatives with excellent enantioselectivity, achieving values up to 95% e.e. These findings underscore the potential of this MOF-based organopalladium nanocomposite as an efficient, reusable, and selective heterogeneous catalyst for the sustainable synthesis of valuable enantiomerically enriched biaryl compounds.

Accurate prediction of structure-property relationships in organic light-emitting diode (OLED) materials requires computational approaches that can efficiently capture conformational flexibility, dynamic disorder, and chemically diverse bonding environments. In this work, we demonstrate the application of machine-learning force fields (MLFFs) based on a message passing network with iterative charge equilibration (MPNICE)42 for predictive modeling of OLED materials. Trained on high-level electronic-structure data and incorporating iterative charge equilibration and long-range electrostatics, the MLFF framework enables rapid geometry optimization and molecular dynamics simulations with near quantum-mechanical accuracy. We show that MPNICE-optimized geometries closely reproduce density functional theory (DFT) reference structures across a diverse set of organic OLED materials, while reducing computational cost by orders of magnitude. This efficiency enables high-throughput screening workflows in which chemically enumerated molecular libraries are rapidly optimized and subsequently subjected to DFT post-processing calculations to evaluate key electronic properties. The approach is further validated through isomerization and conformational analyses, where MPNICE-based sampling accurately captures relative energetics and thermally accessible structural landscapes. Beyond static properties, we demonstrate how MPNICE-driven molecular dynamics simulations provide direct insight into the impact of molecular dynamics on optoelectronic response. For representative organometallic emitters, ensemble-averaged excited-state calculations performed on snapshots extracted from MLFF trajectories yield triplet energy distributions and absorption spectra in good agreement with experimentally measured solution-phase spectra, reproducing both peak positions and spectral broadening. Collectively, these results establish MPNICE-based machine-learning force fields as a scalable and physically grounded platform for data-driven OLED materials design and accelerated optimization of next-generation optoelectronic systems.

Unveiling the intramolecular photophysical transitions and intrinsic excited-state dynamics of organometallic complexes is of critical importance yet remains challenging. Herein, two platinum (II)-acetylide triads, namely Pt-1 bearing the triethylphosphine ligands and Pt-2 with the triphenylphosphine ligands, were rationally synthesized and investigated comprehensively. The NMR shielding phenomena of Pt(II) atoms with dense extranuclear electrons are elucidated properly through comparative studies on a reference analogue, BDT-TPA. The rigid planar molecular geometries endow the triads with extended π-conjugation, which promotes efficient ligand-to-metal charge transfer (LMCT) and ligand-to-ligand charge transfer (LLCT). Furthermore, a significant effect of Pt(II)-acetylide d-π coordination, ligand aromaticity, and steric hindrance on the steady state and nonlinear optical properties are also elucidated comparatively. Benefiting from strong spin-orbit coupling and ligand-mediated conjugation, both Pt(II)-acetylide triads exhibit enhanced intersystem crossing rates and prolonged triplet-state lifetimes. Notably, Pt-2 displays a maximum two-photon absorption cross-section of 1830 GM in THF upon femtosecond excitation at 650 nm, which is obviously higher than that of 980 GM at 775 nm observed for BDT-TPA. High-performance optical power limiting assessments based on the two-photon absorption mechanism reveal that both triads possess low onset thresholds around 0.06 J·cm-2 and favorable limiting thresholds around 0.25 J·cm-2. Theoretical calculations further correlate the superior nonlinear optical performance with efficient excited-state absorption as well as prominent LMCT characteristics. This study not only affords mechanistic insights into the intrinsic photophysics of the Pt(II)-acetylide complexes but also sheds light on the potential nonlinear optical applications.

In this paper, we present a new software suite dedicated to the study and analysis of chiroptical signals and their nature. Beyond the simple evaluation of dipolar moments associated with either electronic or vibrational transitions, the tools it provides are able to compute and represent transition current densities (TCDs), which are directly connected to the electronic contribution to dipole transition moments. By mapping the corresponding vector fields into the real space, details on the sign and magnitude of the rotational strengths can be revealed in terms of localized current patterns on atoms, bonds, and functional groups, offering a unique view into the origins of chiroptical signatures. The software, open-source, is composed of two units: one to generate the fields from standard electronic structure calculations, and a visualization library that supports different representations to highlight, in the most suitable way, the influence of local regions in the systems under study on the overall chiral response. The capabilities of these tools are illustrated through a variety of cases, considering organic and organometallic molecules, closed- and open-shell species, under electronic and vibrational transitions. By making TCD analysis routine for a large range of molecular systems, this suite bridges the gap between black-box simulations of electronic and vibrational circular dichroism and chemically intuitive interpretations of molecular chirality.

Ruthenium functionalized organometallic nanoparticles (Hb@Ru NPs) ca. 10 nm in size, containing crystalline Ru phases were synthesized by a new, single-stage hydrothermal protocol using hemoglobin (Hb) as the skeleton. Compared to currently reported nanozymes, Ru@Hb NPs demonstrated enhanced catalase- and and peroxidase-mimicking activities, produced superoxide (O2•-) and singlet oxygen (1O2) radicals and showed significant glutathione depletion. The maximum substrate consumption rates of 107.5 mM mg-1s-1 and 6.94 µM mg-1s-1, were obtained for catalase-like and peroxidase-like activities, respectively. Hb@Ru NPs exhibited ruthenium induced nanomotor behavior which was utilized to enhance the interaction between tumor cells and nanozyme. Photothermal conversion behavior of Hb@Ru NPs was demonstrated with the temperature elevations of up to 29 °C under NIR laser irradiation. Therapeutic potential of Hb@Ru NPs was evaluated using T98G glioblastoma and HepG2 cells. In-vitro combinatorial photothermal/chemodynamic therapy (PTT&CDT) with T98G cells achieved up to 92.7% cell death, with effective intracellular ROS formation and yielded an apoptotic rate of 63.32%, as determined by flow cytometry. TUNEL staining demonstrated that Hb@Ru NPs significantly induced DNA fragmentation in T98G cells by combined PTT&CDT via producing the most pronounced apoptotic response. PTT&CDT with Hb@Ru NPs also suppressed the migration and proliferation of glioblastoma cells, significantly inhibiting the wound closure in stratch assay.

The microporous nature of metal-organic frameworks (MOFs) often limits their capacity to incorporate large molecular guests, such as organometallic catalysts. In this work, we demonstrate a defect-engineering strategy for the Zr-based MOF UiO-66 to generate hierarchical pore structures capable of hosting the bulky Lehn-type complex [Re(bpy-4-COOH)(CO)3Cl]. By introducing missing-linker and missing-cluster defects-both during synthesis and through a selective ligand removal (SeLiRe) process-we modulate the framework's pore structure and volume. Using a post-synthetic modification approach, 2,2'-bipyridine-4-carboxylic acid (bpy-4-COOH) is anchored into the MOF structure via solvent-assisted ligand incorporation, followed by complexation with [Re(CO)5Cl]. A comprehensive suite of characterization techniques including TGA, Ar-physisorption, STEM-EDX, solid-state NMR, XAS and other spectroscopic methods confirmed the formation and uniform distribution of the Re-complex within the MOF porosity. Our results show that the introduced defects and the associated creation of mesoporosity are essential for successful incorporation of the large Re-complex, while nearly defect-free UiO-66 cannot be modified with the ligand post-synthetically. The use of the SeLiRe process enables us to gain reasonable control over the amount of the Re-complex inside the MOF and leads to a homogeneous distribution throughout the particles. Photocatalytic CO2RR experiments show CO as the main product with high selectivity when using TEOA as a sacrificial agent. This work demonstrates the potential of engineering hierarchical porosity in MOFs for immobilizing large, catalytically active molecular species in a stable and well-defined environment.

The selective cleavage of carbon-carbon (C-C) bonds has emerged as a powerful tool for molecular deconstruction and skeletal editing. However, the inherent strength and low polarity of C-C bonds render their selective scission a formidable challenge. Alkenes are some of the most important chemicals in the chemical industry and synthetic community. Selective deconstructive functionalization of alkenes to produce densely functionalized molecular scaffolds is highly attractive but challenging. This review focuses on the development of C-C bond functionalization of olefins. While traditional approaches have predominantly involved cleavage of the double bond itself, recent advances have opened two distinct and complementary pathways: (1) the selective cleavage of robust σ-bonds adjacent to the double bond, including C(vinyl)-C and allylic C-C linkages, while preserving the valuable alkene moiety and (2) the transformative cleavage and reconstruction of the double bond through novel processes such as single-atom (nitrogen or carbon) insertion, moving beyond conventional metathesis. This review comprehensively summarizes these groundbreaking developments, highlighting the mechanistic principles and synthetic applications that are expanding the toolbox for complex molecule synthesis and editing.

This work reports an efficient and straightforward cross-coupling method for synthesizing thioamide derivatives from dithiocarbamates and organoaluminum or organotitanium reagents, catalyzed by 6 mol % Pd(acac)2 or Pd(OAc)2 with 8 mol % DPPY. Under optimized conditions, the reactions afford thioamides in 18-96 and 14-97% yields, respectively. The protocol shows excellent functional group tolerance toward allyl, cyano, ketal, and electronically diverse aryl and heterocyclic organometallic reagents. Notably, bioactive thioamides bearing 4-(bis(4-fluorophenyl)methyl)piperazine and triazole units are successfully constructed. This approach avoids expensive Ir/Rh catalysts, requires no additional base, and remains efficient at gram scale, thus representing a practical synthetic route to thioamide derivatives. A plausible catalytic cycle is proposed based on experimental observations.

LOHC (Liquid Organic Hydrogen Carrier) systems have emerged as a promising strategy for hydrogen storage and distribution. Among these, N-Heterocycles stand out due to their high hydrogen capacity. Their photocatalytic dehydrogenation has attracted significant attention due to the environmentally friendly conditions under which the reaction can proceed. We report here a new hybrid plasmonic material in which a covalent organic framework (COF) serves as a stabilizing matrix for gold nanoparticles, grafted in situ via an organometallic approach, with sizes ranging from 2 to 4 nm. We have employed the synthesized material as a recyclable photocatalyst in a light-mediated dehydrogenation of N-Heterocycles. This new carbon-based semiconductor photocatalyst also introduces a novel photocatalyst capable of generating both dehydrogenation and hydrogenation products by simply changing the reaction conditions, offering a significant advance for hydrogen storage.

A relay catalytic system that integrates visible-light-enabled Ir-catalyzed asymmetric allylic etherification and dearomative [2 + 2] photocycloaddition has been developed. Unlike conventional ground-state asymmetric allylic dearomatization, this strategy takes advantage of the reactivity of triplet-state indoles. A diverse array of thermally disfavored cyclobutane-fused indolines was achieved in up to 92% yield with excellent diastereo- and enantioselectivities (up to >20:1 dr, >99% ee). Mechanistic studies, including control experiments and intermediate isolation, revealed that the irradiation of CHCl3 with blue LEDs generates HCl in situ, promoting the allylic substitution step. Kinetic analysis and "same excess" experiments indicated that photocycloaddition accelerates the preceding allylic substitution by consuming the allyl ether intermediate, thereby enabling the relay catalysis to achieve a synergistic "1 + 1 > 2" effect.

The integration of fundamental redox and Lewis acid manifolds in catalysis is a pivotal goal in synthetic chemistry, promising to unlock unconventional reactivity. It typically requires two distinct metals as a single metal usually performs only one role. Therefore, achieving both functions from a single metal precursor represents an attractive, yet challenging, goal. Herein, we address this challenge through the rational design of a multifunctional ligand that features complementary coordination units for differentiating two identical metals to perform distinct functions. This ligand enables the assembly of a dinuclear Ni catalyst, wherein one Ni center acts as a Lewis acid, while the second one operates as a redox-active site. This cooperative system achieves an enantioselective hydroalkoxylation of enamides with alcohols, delivering a broad range of valuable acyclic N,O-acetals in high yields and enantioselectivities (up to 98% ee). This work opens a new avenue for the design of advanced catalytic systems.

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The 2-aryl benzofuran-3-ones serve as pivotal scaffolds in natural products and bioactive molecules, yet their synthesis and subsequent asymmetric functionalization are hindered by multi-step protocols and the lability of their derivatives lacking electron-rich substituents on the aromatic ring of benzofuran-3-one core. Herein, we report a phosphinite-mediated, Mo-catalyzed intermolecular asymmetric deoxygenative coupling reaction between 1,2-dicarbonyl compounds and 3-(methoxymethyl)indoles, thus providing a series of chiral 2-aryl benzofuran-3-ones with a chiral quaternary carbon center with generally good yields and enantioselectivities. Mechanistic studies reveal that phosphinite and the Mo-complex synergistically promote the in situ generation of key intermediates, while the formally tetravalent mononuclear Mo-complex serves as the key species governing the enantioselectivity of the reaction. This work expands the application of chiral salen-Mo catalysts in asymmetric catalysis, offering an efficient route to valuable chiral benzofuranone derivatives.

Synthetic catalytic antioxidants offer attractive alternatives to enzymatic redox regulators, yet their biological application is frequently limited by poor stability, formulation challenges, and insufficient control over intracellular localization. Here, we report a lipid conjugation strategy that enables the covalent integration of manganese Salen (EUK) catalysts into phospholipid membranes. A modular synthetic route is established in which a carboxylate-functionalized EUK derivative is coupled to an amine-terminated phospholipid tail, yielding a structurally defined phospholipid-EUK conjugate that retains catalytic activity upon liposome formulation, with controlled catalyst loading and long-term colloidal integrity. The resulting liposomes exhibit efficient catalytic degradation of reactive oxygen species (ROS) with activity scaling with conjugate content. Importantly, covalent anchoring of the catalyst within the lipid bilayer prevents aggregation and precipitation observed for non-conjugated analogues. Using an acetaminophen challenged steatotic HepaRG cell model, we demonstrate that lipid conjugation enables intracellular delivery of the catalyst and sustained reduction of elevated ROS levels without inducing cytotoxicity. This effort establishes a chemically precise approach for positioning organometallic catalysts within biomimetic membranes and highlights these conjugates as versatile platforms for controlled intracellular redox modulation.

In this study, we performed computational studies on two tetradentate ligand precursors and their corresponding Pt(II) and Pd(II) metal complexes containing fused 6/5/6 metallocycles, whose synthesis has been previously reported. We analyzed how the metallophilic interactions, molecular geometry, and π-π stacking influence the optoelectronic and photophysical properties of square-planar Pt(II) and Pd(II) complexes in dimeric forms involved in spin-flip transition using density functional theory (DFT) and time-dependent DFT (TD-DFT) at the M06-2X level of theory with Grimme's D3 dispersion correction. These metal-organic complexes exhibit distinct optical and excited-state properties, resulting from the interaction between the inorganic metal center and the organic ligand. The absorption and emission properties of these complexes were investigated, along with calculations of radiative rate constants, making them efficient and reliable triplet emitters for OLED applications. We also computed their phosphorescence lifetimes and compared them with available experimental data.