European Journal of Inorganic Chemistry最新文献

A family of [Co(N–N)₃]³⁺ complexes (where N–N = 2,2′-bipyridine or 1,10-phenanthroline derivatives) was developed as earth-abundant multifunctional antimicrobial photoinitiators for the generation of biocompatible hydrogels. A facile, robust assembly-followed-by-oxidation approach was used to generate eight [Co(N–N)₃](Ce(NO₃)₆) complexes. To further showcase the synthetic utility of the method, two [Co(N–N–N)₂](Ce(NO₃)₆) complexes (where N–N–N = tridentate polypyridyl ligand) were also synthesised. All the complexes studied proved to be water-soluble. The Co(III) complexes were characterised using ¹H and ¹³C{¹H} nuclear magnetic resonance spectroscopy, elemental analysis and electrospray ionisation mass spectrometry. Additionally, all ten complexes were structurally characterised using X-ray crystallography. The electronic properties of the family of complexes were examined using UV–Vis and Raman spectroscopy, density functional theory calculations and cyclic voltammetry and could be tuned based on the ligand substituents. Efforts to use the [Co(N–N)₃](Ce(NO₃)₆) complexes as photoinitiators for the generation of biocompatible hydrogels from either gelatin methacrylate (Gel-MA) or polyvinyl alcohol methacrylate (PVA-MA) were unsuccessful. However, [Co(dmobipy)₃]³⁺ (where dmobipy = 4,4′-dimethoxy-2,2′-bipyridine) was found to promote gel formation from a gelatin-norbornene (GelNB) macromer under step-growth thiol-ene crosslinking conditions. The antibacterial properties of the Co(III) complexes were also examined. Several of the more hydrophobic complexes were active against a range of Gram-positive and Gram-negative bacteria.

The global climate crisis and carbon neutrality imperatives are urgently advancing CO₂ emission mitigation and resource utilization technologies to critical research frontiers, with photothermal cocatalysis emerging as a transformative approach due to its inherent sustainability and energy efficiency. This review examines recent breakthroughs in cerium oxide (CeO₂)-based catalysts, systematically analyzing their intrinsic catalytic advantages while addressing fundamental limitations including narrow spectral response, high CO₂ activation barriers, and limited product selectivity. State-of-the-art modification strategies—encompassing precision nanostructuring, rational elemental doping, optimized strong metal–support interactions, oxygen vacancy engineering, heterojunction band alignment, and single-atom/nanocluster active site design—synergistically enhance light harvesting, promote charge carrier separation/migration, and improve CO₂ conversion kinetics with superior selectivity. Notwithstanding these advances, persistent challenges in long-term stability, targeted synthesis of high-value products, and scalable implementation necessitate future efforts to decipher multifield photothermal-chemical energy coupling mechanisms, develop manufacturing protocols for ultrastable catalysts, and integrate atomic-scale active site design with reactor-scale engineering applications.

In this article, isomeric tetra-cationic porphyrins with rhenium(I)-carbonyl-phenanthroline complexes at the peripheral N-pyridyl positions 3ReP and 4ReP were evaluated for structural characterization, photophysical properties, theoretical calculations, electrochemical behavior, and photobiological properties. Furthermore, photostability, reactive oxygen species generation, and binding properties on bovine serum albumin protein were assessed using absorption, steady-state, and time-resolved fluorescence emission, with molecular docking analysis.

Marine mussel byssus is recognized for its capacity to accumulate trace metals from seawater including metallic radionuclides. This study deals with uranium and neptunium, two actinides involved in the electronuclear cycle. We propose to elucidate the underlying molecular mechanisms at the origin of uranium and neptunium uptake by the byssus threads of mussel using model systems of increasing molecular complexity: PEG–DOPA (4-arm polyethylene glycol–dihydroxyphenylalanine), purified mfp-1 (mussel foot protein-1), and native byssus. Ex vivo sorption isotherms display a linear adsorption behavior at environmentally relevant concentrations, reflected in high uranium concentration factors that emphasize the byssus as an efficient passive accumulator. Extended X-ray absorption fine structure analysis showed that uranium (uranyl(VI)) coordinates through oxygen donors ligands, consistent with chelation by catechols in mfp-1 and byssus. X-ray absorption near edge structure (XANES) confirmed that uranyl(VI) remained unreduced in all systems. For neptunium (neptunyl(V)), UV–Vis–NIR spectra and XANES both revealed partial reduction of neptunyl(V) to Np(IV) in the presence of mfp-1, while PEG–DOPA induced no such reduction, suggesting the presence of redox-active moieties in the mfp-1. These findings advance our understanding of uranium and neptunium accumulation in mussel byssus, highlighting the central role of mfps and their catechol-rich domains in selective and redox-active actinide binding.

Natural polyphenols such as rosmarinic acid (RA) are gaining attention for their antioxidant, anti-inflammatory, and neuroprotective properties, attributed in part to their ability to chelate redox-active metals. While RA's interactions with Cu(II) have been linked to modulation of amyloid beta (Aβ) aggregation and redox cycling, its coordination with Zn(II)—a key player in Aβ aggregation but redox-inert—remains poorly understood. Given that Zn(II) stabilizes toxic Aβ oligomers and is abundant in amyloid plaques, clarifying whether RA can modulate Zn(II)-Aβ interactions is of high interest. Here, we systematically investigated RA's coordination behavior toward Zn(II) under physiologically relevant conditions, both alone and in the presence of Aβ. Using NMR and UV–vis spectroscopy, we characterized RA-Zn(II) complex formation and explored how RA influences Zn(II)-mediated Aβ associations. These findings provide new insights into the molecular basis of RA's potential neuroprotective effects and underscore the importance of targeting metal–amyloid interactions in Alzheimer's disease.

N-heterocyclic carbene (NHC) ligands featuring functional groups at remote positions allowing for electronic modifications were synthesized and their steric and electronic properties were investigated. The NHC ligands are found to possess comparable steric profiles while displaying similar, but varying electron donating capabilities. Palladium complexes coordinated to these ligands were synthesized, characterized, and investigated in the Buchwald–Hartwig Amination (BHA) of aryl chlorides under both strongly basic and weakly basic conditions. In both cases, we find that ligands possessing more electron donating substituents are more active in this transformation. We further report weakly basic conditions which gives the desired aminated product in high yield with low catalyst loading (0.5–2.0 mol%) that are more tolerant to base sensitive functional groups.

Carbon is well-known to support highly active Type II NiMoS catalysts for hydrodesulfurization. However, compared to the industrially applied Al₂O₃, the synthesis of highly dispersed active sites on carbon, unrestricted to weak carbon-metal interactions, is yet to be explored. Herein, we reported a cetyltrimethylammonium bromide (CTAB) assisted adsorption method for synthesis of highly dispersed NiMoS/C_SAP-CTAB catalyst for efficacy HDS of sluggish dibenzothiophene (DBT) and 4,6-dimethyl-dibenzothiophene (4,6-DMDBT). Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), Brunauer–Emmett–Teller (BET), scanning electron microscopy energy dispersive X-Ray Spectroscopy (SEM-EDX), inductively coupled plasma-optical emission spectrometer (ICP-OES), X-ray photoelectron spectroscopy (XPS) and transmission electron microscope (TEM) characterizations demonstrate the crucial role of electrostatic attractions between cationic CTAB and anionic molybdates for dispersion of molybdate ions and resisting metal loss during the acid washing sodium removal process. Importantly, upon sulfidation activation, the well-structured micropores and highly dispersed Type II active NiMoS sites were confirmed. More importantly, the optimized NiMo/C_SAP-CTAB catalyst demonstrated a turnover frequency of 3.61 h⁻¹ for converting challenging 4,6-DMDBT, 29% and 473% improvement compared to catalysts based on Al₂O₃ and general carbon, thus highly promising for practical applications.

Uranyl complexes of monohalogenated naphthylsalophen ligands (fluorinated (H₂L₁), chlorinated (H₂L₂), and brominated (H₂L₃)) and their redox properties are described. Each complex demonstrates a unique effect upon the coordination of an anion. Acetate coordination, resulting in increased stabilization of the U(VI) oxidation state, was observed as a shift in the apparent uranium reduction potential to more negative values. Template synthesis with uranyl acetate enabled the synthesis of the complexes [Net₃][UO₂(OAc)L₁]- [Net₃][UO₂(OAc)L₃]. While the synthesis of UO₂(Solvent)L₁- UO₂(Solvent)L₃ requires the addition of uranyl nitrate to each ligand with heat, investigation of the electrochemical properties of the metal complexes through cyclic voltammetry displays redox features beyond ligand-centered reductions, with halogen trends and U-L substituents playing a role in the uranium redox behavior. Switching the acetate with solvent molecules reveals quasi and reversible waves attributable to U(V)/U(VI). Spectrochemical and X-ray crystallographic studies allow for a closer look at inner-sphere interactions.

An interesting telluro-phosphate compound, Ba₂Zn₂TeP₂O_11, was prepared employing traditional solid-state chemistry method. The transition-metal-substituted (Ba/Ca/Pb)₂Zn_2-xM_xTe(P/V)₂O₁₁ (M =  Co, Ni, Cu, Mg) compounds, characterized employing powder X-ray diffraction, show bright unique color. The structural studies have been done using X-ray photoelectron spectroscopy and Raman spectroscopy. The compounds exhibit reasonably high dielectric constants with low dielectric loss. The Ba₂ZnCoTeP₂O₁₁ and Ba₂ZnNiTeP₂O₁₁ compounds exhibit antiferromagnetic behavior, while the Ba₂ZnCuTeP₂O₁₁ compound exhibits paramagnetic behavior. A series of single-phase color tunable Ba₂Zn₂TeP₂O₁₁: RE³⁺ (RE =  Eu, Tb, and Tm) phosphors have been prepared and characterized, employing photoluminescence studies. The substituted compounds,Ba₂Zn₂TeP₂O₁₁: Eu³⁺, Ba₂Zn₂TeP₂O₁₁: Tb³⁺, and Ba₂Zn₂TeP₂O₁₁: Tm³⁺ exhibit characteristic emissions of Eu³⁺ (red), Tb³⁺ (green), and Tm³⁺ (blue), respectively. By carefully adjusting the concentration of Eu³⁺ ions in the Ba₂Zn₂TeP₂O₁₁: 2% Tm³⁺, 2% Tb³⁺, and x % Eu³⁺ (x =  0, 1, 2, 3, 4, 5, 6) system, we achieved white light emission. It also demonstrates selective and sensitive detection of nitroaromatics (nitrobenzene and 4-nitrophenol) by turn-off luminescence.

We present an X-band EPR and density functional theory (DFT) study of five fully-chelated Co(II)complexes, in order to assess the differences in their solid state and frozen solution EPR, and to examine the accuracy of the DFT-predicted EPR parameters. The complexes represent two meridional bis-tridentate complexes of bispyrazolylpyridines, and three tris-bidentate complexes. Spectra for the meridional complexes show substantial broadening in frozen solution that can be attributed to structural disorder, without significant changes in the magnetic parameters. The two tris-bidentate complexes that do not form isomers also give rise to broader spectra in frozen solution, but the features collapse into a more axial pattern, indicating a reduction in E/D. The fifth complex forms three structural isomers, based on the juxtaposition of its pendant groups. DFT was used to predict the spectra of the individual isomers, and produced a sum simulation that reasonably matched its complex solid-state spectrum. Data are also presented that show the parallel mode response of these systems is unusually strong, and that the ability to observe these signals depends on sublevel mixing, and correlates well with the magnitude of E/D.