Inorganic Chemistry最新文献

U-donor bond lengths in uranyl coordination complexesdirectlyreflect metal–ligand interaction strength and provide importantstructural parameters for evaluating ligand recognition, selectivecomplexation, and extraction/adsorption system design. To enable bond-levelprediction, this study developed a DFT-derived machine learning frameworkfor predicting U-donor bond lengths. A data set containing 15,177coordination structures and 26,798 U-donor bond length data pointswas constructed from 3,330 unique ligands under a unified computationalprotocol. Five categories of models, including linear models, support-vector-basedmodels, ensemble tree models, descriptor-based neural networks, andgraph neural networks, were evaluated to compare representation strategies.Among descriptor-based models, XGBoost achieved the best performance,with R², RMSE, and MAE values of 0.793,0.057 Å, and 0.039 Å, respectively. Among graph neural networks,DimeNet++ performed best, with R², RMSE,and MAE values of 0.821, 0.051 Å, and 0.036 Å. Functional-group-basedevaluation and SHAP analysis indicated that donor atom type, neighboringatomic environment, local electronegativity difference, and localgeometric features are key factors controlling U-donor bond lengthvariations. External validation using unseen functional groups anduranyl structures demonstrated model generalization beyond the trainingspace. This work provides a bond-level data set and a data-drivenstrategy for rapid U-donor bond length prediction and ligand screeningin actinide coordination systems.

Selectiverecognition of iodide remains challenging because ofits large ionic radius, weak hydration, and high polarizability. Herein,we report two tetraphenylethene-based Pd₂L₄ metallacagesfeaturing cyano-vinylene spacers for confined-cavity engineering andiodide recognition. Structural analysis reveals that subtle ligandvariation leads to distinct supramolecular microenvironments, in whichinward-oriented cyano-vinylic hydrogen atoms generate an electron-deficientcavity favorable for anion binding. Both metallacages exhibit aggregation-inducedemission and pronounced photoluminescence quenching in response toiodide, with high selectivity over competing anions. Solid-state sensingstrips enable rapid, concentration-dependent visual iodide detectionwith minimal interference from counter cations or pH variations.

Photothermal conversion has found broad applicationsranging frombiomedicine to chemical synthesis; however, the development of stable,non-noble metal photothermal agents remains a significant challenge.Herein, we report a class of mononuclear Mn(III) complexes bearingcarbazole-bridged N-heterocyclic carbene (NHC) ligands(Mn-1–Mn-3). The carbazole-bridgedbis-NHC framework affords tunable visible-light absorption, with Mn-3 exhibiting the most pronounced absorption in the long-wavelengthvisible region. Mn-3 shows good photothermal performance,reaching a temperature of 76 °C under 635 nm irradiation. Furthermore,we demonstrate the utility of Mn-3 as a photothermalcatalyst for the C–N coupling of bromobenzene and pyrrolidine.This work not only presents a rare example of manganese-based molecularphotothermal agents but also highlights a viable strategy for utilizingearth-abundant manganese complexes in photothermally driven organicsynthesis.

Solid-state ion exchange (SSIE) method generates minimalwastewaterand provides high ion-exchange rates, making it an emerging strategyfor tuning zeolitic structures and properties. However, the mechanisticunderstanding involving ionic diffusion in zeolites remains unclear.In this work, we used Y zeolite as the proof-of-concept case, demonstratingthat FeY catalysts prepared via the SSIE method exhibit superior catalyticactivity for ketalization of glycerol and cyclohexanone. As one ofthe key findings, SSIE induces significantly less structural damageto the zeolite framework than ion exchange in liquid medium, whereFe³⁺ unusually migrates from supercages to β cagesin the solid state. Na⁺ species associated with AlO₄ tetrahedra are replaced by Fe³⁺, forming isolatedFe³⁺ and oligomeric Fe_xO_y species that correspond to [Fe(OH)₂]⁺ and [HO-Fe-O-Fe-OH]²⁺. Consequently, theintroduction of Fe³⁺ also modulates Lewis acidity, moreimportantly, generating additional Brønsted acid sites. IsolatedFe³⁺ species are favorably formulated during solid-statediffusion. Computational studies further reveal that the acidic hydroxylgroups associated with isolated Fe³⁺ species are the intrinsicactive sites for glycerol ketalization. The mechanistic insights provideboth experimental and theoretical foundations for designing next-generationzeolite catalysts for the green synthesis of bio-based specialty chemicals.

Covalent organic polymers (COPs) have attracted considerableattentionas electrocatalysts because of their tunable structures, high porosity,and abundant functional sites, yet their practical application isoften limited by poor electrical conductivity. Herein, conductivemetalloporphyrin-based COP hybrids were synthesized through a quaternization-inducedpolymerization strategy in the presence of multi-walled carbon nanotubes(MWCNTs). The resultant FeTPyPCOP@MWCNTs and NiTPyPCOP@MWCNTs integratemetalloporphyrin coordination sites, a porous polymer framework, anda conductive carbon network within a single architecture. A directcomparison between the two materials reveals that FeTPyPCOP@MWCNTsexhibit superior electrocatalytic activity toward water splitting,highlighting the important influence of the coordinated metal center.FeTPyPCOP@MWCNTs requires overpotentials of only 117 mV for the hydrogenevolution reaction (HER) and 241 mV for the oxygen evolution reaction(OER) at 10 mA cm^–2. In a two-electrode electrolyzer,it delivers 10 mA cm^–2 at a cell voltage of 1.56V, together with excellent durability and near-quantitative Faradaicefficiency. This work demonstrates that combining metalloporphyrincoordination environments with conductive polymer/carbon architecturesis an effective strategy for developing efficient bifunctional electrocatalystsfor overall water splitting.

Starting from the iron(II) complex,[(L¹)Fe^II(CH₃CN)₂]⁺ (1), ofthe tris(2-pyridylthio)methanido (L¹) ligand, an iron(II)-benzilatecomplex, [(L²)Fe^II(PyS)(benzilate)] (2), (L² = bis(2-pyridylthio)carbene and PyS = pyridine-2-thiolate)was isolated and characterized. Single crystal X-ray diffraction studiesof 2 reveal that the iron(II) center is coordinated bythe carbene ligand (L²) in a tridentate N₂Cmode, along with a bidentate PyS formed upon C–S bond cleavageof L¹. A solvent-dependent carbene-carbanion equilibriumfor L¹ is favored toward carbene in the presence of anionicbenzilate in dichloromethane, leading to the formation of 2. Complex 2, upon reaction with dioxygen, undergoesa rearrangement of the carbene (L²) to carbanion (L¹), ultimately affording an iron(III)-benzilate complex, [(L¹)Fe^III(benzilate)] (3). Intriguingly,the iron(III)-benzilate complex in the presence of complex 1 reacts with dioxygen, leading to complete decarboxylation of thecoordinated benzilate. This observation suggested possible cooperativeinvolvement of a dimeric intermediate in the reaction pathway. Consistentwith this hypothesis, a benzilate-bridged mixed-valent diiron, [(L¹)Fe^III(benzilate)(L²)Fe^II(PyS)]⁺ (4), was isolated independently,and its dioxygen reactivity was evaluated. Expectedly, complex 4 undergoes quantitative decarboxylation upon reaction withdioxygen. These findings highlight the importance of solvent-dependentrearrangement capability of the carbanionic ligand in directing dioxygenactivation and benzilate decarboxylation at the iron center.

We herein report the synthesis and characterization ofa seriesof PNP-coordinated rhodium vinylidene complexes with a carbazole-basedPNP pincer ligand framework. The availability of the reactive 14-valenceelectron [(PNP)Rh^I] complex 1 allowed a step-by-stepmonitoring of the metal-centered conversion of the terminal alkyneto the coordinated vinylidene. In a first step, the R–C≡CH(R = H, Ph, C₆H₄F, cyclohex-1-enyl) substrateoxidatively added to 1 to form an isolable correspondingalkynyl(hydrido)rhodium(III) intermediate (2a–5a), from which intramolecular conversion to the vinylidenecomplexes 2b–5b occurred. The equilibriumof 2a–5a with the preceding η²-π-coordinated alkyne complexes was not observed, thelatter being destabilized by >5 kcal/mol as indicated by DFT modeling.This enabled easy monitoring of the vinylidene generation via a 1,3-hydrogenshift mechanism, as evidenced by kinetic measurements in combinationwith DFT calculations. Some aspects of the reactivity of the parentRh=C=CH₂ vinylidene complex 2b toward electrophilesand nucleophiles was investigated, uncovering a remarkable inertnessof the vinylidene-rhodium unit in 2b.

Efficientremoval of iodate (IO₃^–)from radioactive liquid waste is highly desirable for radioactivewaste management and environmental protection but remains a formidablechallenge due to the low adsorption capacity or insufficient removaldepth resulting from the weak affinity of conventional single-functionadsorbents. Here, we report a redox-active metal–sulfide framework(SCU-SnS) that enables the highly efficient decontamination of IO₃^– through a synergistic effect: efficientreduction of IO₃^– to I^– by S^2– sites, combined with an extremely highbinding affinity between Sn⁴⁺ sites and the resulting I^–. Benefiting from this synergistic effect of redoxand iodination reactions, SCU-SnS features both an exceptionally highdistribution coefficient (K_d = 1.58 ×10⁶ mL/g) and a remarkable adsorption capacity of 1022.8mg/g for IO₃^– removal. Notably, SCU-SnSdemonstrates an unparalleled selectivity, capable of nearly quantitativeremoval of IO₃^– in the coexistence ofa 100-fold excess of various competing anions, including Cl^–, NO₃^–, CO₃^2–, and SO₄^2–. This synergistic strategynot only delivers a promising adsorbent for IO₃^– decontamination under highly competitive environments but also inspiresan alternative approach to designing advanced adsorbents for nuclearwaste management.

Copper phosphosulfides,including Cu₇PS₆ andCu₃PS₄, are important materials for their ionic,electronic, and thermal conductivity properties. However, nanocrystalsof these copper phosphosulfides are surprisingly rare. Here, we showthat both Cu₇PS₆ and Cu₃PS₄ nanocrystals can be synthesized by reacting CuCl, P₂S₅, 1-dodecanethiol, and oleylamine at 250 °C for 1 h,with all reagents playing key roles in the synthesis. Phase selectivityis achieved by controlling reagent concentration, which is relatedto the reaction chemistry that is implicated in the formation of thenanocrystal products. Cu₇PS₆ forms tetrahedron-shapednanocrystals while Cu₃PS₄ forms tetrapods, whichcan be rationalized by crystal structure relationships. The successfulformation of Cu₇PS₆ and Cu₃PS₄ represents an important addition to the library of syntheticallyaccessible nanocrystals with well-defined morphologies.