Applied Organometallic Chemistry最新文献

The transformation of carbon dioxide (CO₂) into high-value-added chemical products constitutes a prospective avenue for constructing a carbon-neutral society and promoting energy storage. For this purpose, the design and synthesis of efficient catalysts for the generation of cyclic carbonates from CO₂ and epoxides is of crucial significance. In the present research, a three-dimensional porous, flower-shaped Ni/Zn-MOFs has been synthesized via a hydrothermal approach. This framework acts as a precursor for the synthesis of the NZC-550 catalyst. The obtained NZC-550 catalyst serves as a retrievable heterogeneous catalyst in the cycloaddition reaction of CO₂ and epoxides, attaining satisfactory outcomes. A series of characterization methods such as XRD, FESEM, TEM, HAADF-STEM-EDS, XPS, and Raman reveal that the NZC-550 catalyst demonstrates remarkable performance in the CO₂ cycloaddition reaction. This could be ascribed to its hierarchical architecture and the cooperative effects between Ni₃ZnC_0.7 alloy and ZnO. Additionally, the NZC-550 catalyst exhibits outstanding stability and activity throughout multiple reaction cycles. It is contended that this bimetallic MOFs-templated methodology furnishes valuable perspectives for the design of catalysts dedicated to CO₂ conversion reactions.

Although silver diamine fluoride (SDF) effectively prevents dental caries, it can cause undesirable tooth discoloration and may be cytotoxic. To address these limitations, we developed a fluoride-based composite that incorporates AgNP-doped metal–organic frameworks (MOFs) with a 5% sodium fluoride (NaF) solution (Ag@MOF-5/F). The AgNPs were anchored onto the nanosheets of synthesized MOF-5 and characterized by scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), X-ray diffraction (XRD), and Fourier-transform infrared spectroscopy (FTIR). Different concentrations of Ag@MOF-5/F (1 to 25,000 ppm) were prepared and assessed for antibacterial activity against Streptococcus mutans (S. mutans) and cytocompatibility with human gingival fibroblasts (HGF-1). The most effective concentrations (400 and 1400 ppm) were evaluated for potential staining of the prepared dentin specimen and compared against 5% NaF and 38% SDF. Ag@MOF-5/F demonstrated potent antibacterial activity with a minimum inhibitory concentration (MIC) and a minimum bactericidal concentration (MBC) against S. mutans at 25 ppm. HGF-1 cell viability remained above 49% at 400 ppm and 37% at 1400 ppm, which indicated enhanced biocompatibility compared with the SDF (23%) and NaF (31%). There was no perceptible tooth discoloration with Ag@MOF-5/F, in contrast to the pronounced black staining caused by SDF. This study introduces a novel Ag@MOF-5/F formulation that combines broad-spectrum antibacterial efficacy with favorable cytocompatibility and superior aesthetic outcomes for caries management.

A novel Nd (III)-containing antimonotungstate [(CH₃)₂NH₂]₅Na₂₁{[Nd₄(tar)₃(OAc)(Sb₂W₂₁O₇₂)₂(H₂O)₁₀]}Cl·34H₂O (NdSbW, H₄tar = tartaric acid), was successfully synthesized via a dual-ligand regulation strategy. NdSbW features planar axisymmetric {Nd₂Sb₂W₂₁} units bridged by three tartaric acid ligands and one acetic acid ligand, forming a 2D layer framework stabilized by sodium ions. Furthermore, NdSbW, as a heterogeneous catalyst, exhibits excellent catalytic activity for the synthesis of benzothiadiazine 1,1-dioxides with high yield under environmentally benign conditions.

Cervical cancer is a distinct form of cancer that impacts women globally, with an annual occurrence of 604 thousand new cases and 341 thousand deaths. The current chemo-therapeutic treatment is limited by drug resistance and concerns about toxicity, highlighting the need for new potent, nontoxic, and cost-effective alternatives. In this work, we synthesized a series of barbituric acid–derived azo dye ligands (L1–L4). All four ligands were confirmed by FTIR and NMR spectroscopy. Among them, L1 forms a stable dinuclear Cu (II) complex (B1), which was comprehensively characterized by UV–Vis, FTIR, SC-XRD, EPR, TGA, and XPS. Azo groups (-N=N-) are reactive organic groups that interact with biomolecules like proteins and nucleic acids to contribute to the biological activity of azo substances. B1 exhibits a GI50 value of 10 μM, indicating significant anticancer potential. It also shows inhibitory properties against bacteria and fungi, suggesting potential antimicrobial impact. Hence, this current study emphasizes the anticancer and antimicrobial capabilities of the synthesized complex. Moreover, the sensitivity of B1 to fluoride ions suggests its capacity to function as a sensor. The remarkable biological activity and sensitivity of B1 indicate its potential for therapeutic and diagnostic purposes, especially in targeting resilient microbial strains, cancer cells (HeLa), and environmental screening.

In the current work, modified Schiff base triazole appended silatrane (6) has been synthesized using the copper(I) catalyzed alkyne azide cycloaddition (CuAAC) approach. The organosilatrane (6) has been utilized for the detection of Al (III) with limit of detection values of 4.7 × 10⁻⁷ M (absorption analysis) and 0.24 × 10⁻⁷ M (fluorescence analysis). The metal–ligand complex binding site has been confirmed by ¹H NMR, FT-IR, and mass spectrometry techniques. The DPPH assay has revealed the antioxidant potential of compound (6) with an IC₅₀ value of 2.09 μM. Chemosensor (6) has responded to anticancer activity, achieving a maximum reduction of cell viability of 77.39% relative to untreated control cells. Additionally, the molecular docking study of ligand (6) with 1B-DNA has been performed, with a binding energy of −8.29 kcal mol⁻¹.

The present study reports the chemical synthesis, spectroscopic characterization, and evaluation of selected biological properties of copper and nickel phthalocyanines bearing hexyl benzoate substituents. The newly synthesized phthalocyanine (Pc) complexes were characterized using Fourier-transform infrared (FT-IR) spectroscopy, UV–Vis spectroscopy, proton nuclear magnetic resonance (1H-NMR) spectroscopy, and mass spectrometry. In addition to their structural analysis, the antioxidant, antidiabetic, antibiofilm, antimicrobial, microbial viability inhibition, and DNA cleavage activities of the 4HEBCu and 4HEBNi compounds were systematically investigated. 4HEBCu and 4HEBNi exhibited 22.35% and 81.29% antioxidant effects at 25 mg/L, respectively, while their antidiabetic activity was highly effective at 100% and 93.82% at 100 mg/L, respectively. All compounds were found to cause complete cleavage of DNA. 4HEBNi was determined to have superior antimicrobial properties compared with 4HEBCu. The compound 4HEBNi demonstrated the highest activity in inhibiting biofilms of S. aureus and P. aeruginosa. In addition, the activity of both compounds in inhibiting biofilm formation also increased after photodynamic therapy. The inhibition of microbial cell viability was 83.97% for 4HEBCu and 98.89% for 4HEBNi against E. coli at 25 mg/L.

We report the design and synthesis of a new pyrimidine-based organoplatinum (II) complex (3), constructed over three consecutive steps starting from 4,6-dichloropyrimidine. This flexible precursor acted as a key acceptor tecton to compose the self-assembly of three distinct ionic [2 + 2] macrocycles (M₁–M₃) in high yields through coordination with neutral N-donor ligands. Comprehensive spectroscopic and analytical techniques such as FT-IR, NMR, and HRMS were employed to validate the purity, symmetry, and structural integrity of the macrocycles. Notably, the appearance of sharp singlets in ³¹P NMR spectra and the presence of a single diffusion trace in ¹H-DOSY NMR unequivocally confirmed the formation of discrete, well-defined assemblies. High-resolution mass spectra further supported this, revealing the signature [M-3NO₃]³⁺ peaks for all macrocycles. MTT assay was performed to evaluate the cytotoxic potential of these compounds against human breast cancer cell line MCF-7 and human normal breast epithelial cell line MCF-10A. The findings revealed that the macrocycles exhibited greater cytotoxicity than the precursor molecule and cisplatin in MCF-7 cells. Furthermore, all the compounds showed much lesser cytotoxicity toward normal MCF-10A cells. These results indicate that self-assembled, charged organoplatinum macrocycles manifest enhanced anticancer potential and may serve as promising scaffolds for the development of next-generation chemotherapeutic agents.

Heavy metal ions pose a significant threat to the environment and human health. Developing a highly sensitive heavy metal ion detection method is desirable. In this study, the Au(I)-catenates were formed in glucoamylase (Glu) and neomycin sulfate (Ne). The polychrome metal nanoparticles (MNPs) were prepared based on the template of Au(I)-catenates. The simple and ultrasensitive visual sensor array for the determination of heavy metal ions was established based on the color information extracted from polychrome MNPs. The addition of heavy metal ions shuttled among Au(I)-catenates in the strong alkaline solution. Through the use of the microwave heating method, the spherical and cubic MNPs of various sizes and colors were synthesized. To fully utilize the polychrome MNPs, a visual sensor was constructed for the detection and discrimination of eight heavy metal ions. The fingerprint-like color response signals correspond to each heavy metal ion and can be distinguished using computer software. The detection limit (0.1 nM) of heavy metal ions discriminated by the sensor is significantly lower than the data reported. The validation of the sensor was carried out by quantitative detection of Hg²⁺ compared with its content in a certified reference material. This array method shows high sensitivity, good anti-interference, and potential in complex media.

Three pairs of chiral lanthanide clusters R-/S-Eu₂-MPA, R-/S-Eu₂-PPA, and R-/S-Eu₂-NPA were synthesized using three pairs of chiral ligands (R-HMPA = (R)-(−)-α-methoxyphenylacetic acid, S-HMPA = (S)-(+)-α-methoxyphenylacetic acid; R-HPPA = R-(−)-2-phenylpropanoic acid, S-HPPA = S-(+)-2-phenylpropanoic acid; R-/S-HNPA = R-/S-2-(6-methoxy-2-naphthol)) with varying steric hindrance and π-conjugation effects, systematically investigating the regulatory mechanism of ligand structure on the chiral environment and the luminescent properties of Ln³⁺. Single-crystal structural analysis reveals that the ligand R-/S-HNPA, featuring an extended π-conjugated naphthyl group, induces the lowest-symmetry coordination geometry for Eu³⁺ ion in R-/S-Eu₂-NPA, resulting in an enhanced luminescence dissymmetry factor (g_lum = ±0.006) compared with R-/S-Eu₂-MPA and R-/S-Eu₂-PPA. Moreover, the additional π–π interactions between R-/S-HNPA and diph (diph = dipyridoacphenazinehemihydratemin) increase the molecular rigidity and effectively suppress non-radiative transitions, thereby elevating the solid-state luminescence quantum yield (Φ_lum) to 13.42% (compared with 6.88% for R-/S-Eu₂-MPA). This work demonstrates that chiral ligand engineering can synergistically regulate both the asymmetry of the coordination field and the supramolecular interactions, offering a promising strategy for the development of high-performance chiral luminescent materials.

New unsymmetrical NCS–pincer Pd(II) complexes incorporating pyrimidine-thioether–functionalized N-heterocyclic carbene (NHC) ligands were synthesized through direct metalation of imidazolium salts and subsequent anion exchange. Their structure was characterized unambiguously by NMR spectroscopy, high-resolution mass spectrometry (HR-MS), and single-crystal X-ray diffraction analysis. These complexes enabled the direct C–H arylation of challenging heteroaromatics (2-acetylthiophene/furan and imidazole derivatives) with aryl bromides under operationally simple conditions (KOAc/DMAc), achieving excellent reactivity (yields up to 99%) and broad substrate scope.