Search Results (644)

A new approach to 5,5-fused heterocyclic derivatives of cyclopentadienylmanganese tricarbonyl and pentamethylruthenocene is presented. 1,2-Dicarbophenoxycyclopentadienyl complexes of manganese and ruthenium were hydrolyzed to 1,2-dicarboxylic acids. Oxalyl chloride converted the acids to chlorocarbonyls, which reacted with bis(trimethylsilyl)sulfide to give the cyclopentadienyl-fused thioanhydrides. Alternatively, dehydration of the diacids with trifluoroacetic anhydride closed the diacids to cyclopentadienyl-fused anhydrides. Treatment of the anhydrides with p-toluidine followed by oxalyl chloride led to cyclopentadienyl-fused carboxylic imides. This approach enables direct comparison of electron-deficient Mn(CO)₃ and electron-rich Ru(Cp*) coordination environments on the 5,5-fused heterocycles. Spectroscopic data reveal systematic downfield NMR shifts and higher infrared carbonyl stretching frequencies for the manganese complexes, consistent with lower electron density in the Mn(CO)₃ compared to Ru(Cp*). Crystallographic analyses confirm that heterocycle fusion occurs without significant perturbation of the metal–cyclopentadienyl geometry. Comparative analysis across the series demonstrates that metal-dependent effects are primarily electronic rather than structural, with the Mn(CO)₃ and Ru(Cp*) fragments modulating electron distribution within the fused ligand framework. Full article

The production of sustainable and cost-effective energy remains a global challenge, with photovoltaic technology emerging as a promising solution. Sensitizers play a key role in electron production in dye-sensitized solar cells, which are emerging photovoltaic devices; thus, different chemical structures have been introduced to achieve the best results. Determining the optimal conditions for the coating and application of dye materials to obtain optimal efficiency and performance is of great importance. For this purpose, an organometallic dye was used to extract the optimal coating conditions. Two factors—ambient temperature during photoanode preparation and anti-aggregation agent concentration—were selected as effective parameters, and the optimal conditions for achieving high efficiency and durability were determined using machine learning. Finally, the findings were analyzed from two perspectives: the preparation of laboratory devices using the selected dye and the evaluation of similar dye materials to validate the proposed optimal conditions. Full article

Organometallic chemistry deals with the synthesis, structure, reactivity, and applications of compounds containing metal–carbon covalent bonds. In recent years, there has been a growing interest in predicting the catalytic activity of organometallics using machine learning. However, the major drawback in developing algorithms that can be used in predicting organometallic reactions is the availability of organometallic reaction data and organometallic filtering tools. The main aim of the current study is to develop organometallic reaction-filtering tools that are crucial for building accurate and effective ML models in organometallic chemistry. Random Forest (RF), K-Nearest Neighbors (kNN), Support Vector Classifiers (SVC), and Multi-Layer Perceptrons (MLP) were employed, using feature subsets selected via Permutation Feature Importance from Morgan fingerprints and MACCS keys. The results demonstrate that the MACCS-based MLP architecture provides the most reliable filtering performance, achieving a superior F1 score of 0.85, a Recall of 0.85, and a high AUC-ROC of 0.837. Furthermore, the MACCS-MLP exhibited the highest predictive confidence, yielding the study’s lowest Log Loss of 0.312. In contrast, while Morgan fingerprints paired with kNN offered a specialized “strict” filter with absolute Precision (1.00), the sparse dimensionality of circular fingerprints generally resulted in lower calibration for probabilistic models. These findings underscore that dense, fragment-based descriptors refined by data-driven feature selection are most effective for identifying complex organometallic motifs. This study successfully provides a validated methodology for building precise filtering tools, establishing a critical foundation for automated catalyst discovery and the expansion of effective machine learning applications in organometallic chemistry. The study is limited to only identifying organometallic reactions and cannot filter based on organometallic reaction types. Future studies should also explore integrating multiple feature representations to classify or cluster the identified organometallic reactions based on the reaction types. Full article

Deuteration provides a controlled perturbation for probing isotope and symmetry effects in organometallic vibrational spectra. Here, density functional theory (DFT) is used to systematically examine the evolution of far-infrared (400–600 cm⁻¹) Fe–Cp vibrational modes in fully protonated, partially deuterated, and fully deuterated ferrocene. All three characteristic modes—the a₂″ torsional mode and the two e₁′ bending modes—exhibit monotonic red-shifts with increasing deuteration. The a₂″ mode shows the largest isotope sensitivity, shifting by ~28 cm⁻¹ across the DFT series, whereas the e₁′ modes shift by ~11–12 cm⁻¹ and undergo symmetry-dependent splitting of up to ~2 cm⁻¹ under partial deuteration. These results establish the a₂″ band as a sensitive probe of the degree of deuteration and the e₁′ splitting as a diagnostic of symmetry reduction. A physics-based AI surrogate model reproduces the overall red-shift trends but deviates at high deuteration, with maximum errors of ~16.6 cm⁻¹, highlighting the limits of reduced-mass scaling. Full article

The ferrocidiphenol family brings together anticancer molecules featuring a [ferrocene-alkene-(p-phenol)₂] motif that can form upon oxidation a quinone methide metabolite targeting cellular proteins. Adding an imide group (imido-ferrocidiphenol) dramatically enhanced the anticancer activity of ferrocidiphenol. We aimed to explore whether molecules with two ferrociphenol motifs connected by bisimide moieties could provide even more effective compounds. Using amino-ferrocidiphenol and commercial bisanhydrides at reflux, for the first time, three symmetrical and bent bis(imido-ferrocidiphenols) were synthesized, with moderate yields, and characterized. However, these compounds were insoluble in most common organic solvents and unstable. This likely explains why their anticancer activity was nil. Full article

Emerging organic pollutants (EOPs) in aquatic environments have attracted increasing attention because many occur at trace levels, undergo transformation during environmental transport, and contribute to poorly resolved mixture risks. Traditional targeted analysis is inherently restricted to predefined compounds, whereas high-resolution mass spectrometry (HRMS)-based full-scan workflows provide broader opportunities for discovering known unknowns and previously unrecognized contaminants. This review critically synthesizes an omics-based analytical framework for aquatic environments, covering sample digitalization, instrumental analysis and acquisition modes, chemical fingerprint/non-target screening, suspect screening, effect-directed analysis, and confidence-based structural identification. Particular emphasis is placed on practical decision points and trade-offs, including dissolved versus particulate-associated analytes, LC-HRMS versus GC-HRMS coverage, hard versus soft ionization, DDA- versus DIA-type acquisition, database dependence, and the persistent difficulty of linking analytical features to toxicological relevance. The review also discusses emerging directions involving artificial intelligence, chemometrics, organometallic contaminants, and microplastic-associated chemicals. By clarifying conceptual boundaries and highlighting current limitations, this article aims to support the development of more critical, transparent, and risk-oriented workflows for the discovery and prioritization of emerging pollutants in aquatic environments. Full article

This article describes a study on the synthesis and annealing processes of thin-film coatings of vanadium oxide on flat, parallel substrates made of quartz glass, sapphire, and silicon, as well as optical fibers using an organometallic precursor, triisopropoxy vanadium (V) oxide. For the first time, optical constants of nanomaterials were estimated in real time during synthesis and subsequent annealed using the lossy-mode resonance effect. The coatings produced in an inert atmosphere after deposition were amorphous, comprising a mixture of VO₂, V₂O₅, V₆O₁₃, and V₃O₅. This method allowed for accurate determination of the threshold temperature for the transformation of oxide mixtures into a monocomponent phase. Optimal conditions for synthesis and annealing were determined for the production of vanadium dioxide (VO₂) and pentoxide (V₂O₅). Morphological changes in coated surfaces were observed as a result of heat treatment. The composition and properties of these samples were studied using optical, terahertz and Raman spectroscopy, as well as temperature-dependent analysis of electrical resistance. The morphology of the coating surface was determined using a scanning electron microscope and an atomic force microscope. The reduction of VO_x to VO₂ was studied in an atmosphere of hydrogen and argon during annealing after deposition, with its effectiveness being compared. It was shown for the first time that the reduction of higher vanadium oxides is due to the presence of elemental carbon in the volume of the material formed from a metalorganic precursor during growth of vanadium oxide. Coatings obtained by annealing in hydrogen had a smaller hysteresis loop width (~5 °C) during phase transition compared to coatings obtained by argon annealing (~9 °C). Both types of coatings demonstrated a 50–60% increase in transmission at 1 THz frequency and in the IR region, accompanied by a 10³–10⁴-fold change in electrical resistance. Full article

Baicalin is a natural compound sourced from Scutellaria baicalensis which possesses various biological activities. To date, a large amount of research has been conducted on the antibacterial activity and related mechanisms of baicalin, making it a promising candidate for new broad-spectrum antibacterial drugs. However, the solubility of baicalin is limited. To improve its solubility and overcome the clinical application bottleneck, researchers have developed various solubilization techniques. Therefore, this article introduces the biological characteristics of baicalin; explores its effects as an antibacterial agent on bacterial biofilms, quorum sensing, virulence factors, inflammatory responses, and the immune system; and discusses the applications of nano-carrier loading technology, cyclodextrin inclusion technology, metal ion coordination and organometallic complexation technology, and dynamic covalent hydrogel assembly technology in improving the solubility of baicalin, thereby enhancing its antibacterial activity. Full article

Background: Breast cancer (BC) remains the most prevalent malignancy among women worldwide, with one in eight at risk during their lifetime. Platinum-based chemotherapeutic drugs, despite of their binding to the DNA of cancer cells, are plagued by toxicity and resistance, necessitating the need for safer and more effective alternatives, such as organometallic complexes. Both synthetic organometallic complexes and natural compounds have attracted attention in this regard. Organotin(IV) complexes are promising chemotherapeutics due to their structural versatility and bioactivity, while vitamins such as Vitamin D (VD) and Vitamin E (VE) exhibit antiproliferative, anti-inflammatory, and antioxidant properties, making them valuable candidates for combination therapy. Methodology: In this study, six novel organotin(IV) dithiocarbamate complexes [LMe₃Sn (Complex 1), LBu₃Sn (Complex 2), LPh₃Sn (Complex 3), LMe₂SnCl (Complex 4), LBu₂SnCl (Complex 5), and L₂Me₂Sn (Complex 6), where L = (E)-4-styrylpiperazine-1-carbodithioate], were synthesized and characterized by FT-IR, ¹H-, ¹³C-NMR, and elemental analysis. Results: Structural studies confirmed penta- and hexacoordination geometries. In silico docking against six BC-related proteins identified Complexes 2 and 4 with both vitamins as promising candidates, exhibiting strong binding affinities, with stable interaction profiles. However, integration of pharmacokinetic, antioxidant, and anti-inflammatory analyses highlighted Complex 4 with both vitamins as the most potent candidate owing to its superior ADME characteristics and balanced biological properties. Subsequent in vitro assays confirmed these findings, as Complex 4 demonstrated strong cytotoxic activity against both MCF-7 (>1.16-fold) and MDA-MB-231 (>1.46-fold) cell lines, surpassing the efficacy of cisplatin. Remarkably, co-administration of VD or VE with Complex 4 further enhanced its anticancer potential, with Chou–Talalay combination index values < 1 (0.66–0.91) indicating a synergistic interaction. Conclusions: Collectively, these results identify Complex 4 as a promising lead compound, and its synergistic activity with natural vitamins may promote cell death, likely through apoptosis induction and modulation of oxidative stress, underscoring its potential as an effective and less toxic therapeutic strategy for breast cancer management. Full article

Quercetin, one of the most abundant flavonoids in nature, has attracted the attention of many researchers due to its chemical and biological properties. A series of metal–quercetin complexes (Cu²⁺, Co²⁺, Zn²⁺, Sn²⁺, Al³⁺, Cd²⁺ and Mg²⁺) were synthesized and systematically characterized by Fourier transform infrared spectroscopy (FTIR), UV-visible spectroscopy (UV–Vis) and nuclear magnetic resonance (NMR). These analyses confirmed that the complexes predominantly form through coordination with the 4-carbonyl group and adjacent phenolic hydroxyls. This induces measurable shifts in the ν(C=O), ν(O–H), and π→π* transition bands relative to free quercetin. The antioxidant capacity of the complexes was evaluated using 2,2-Diphenyl-1-Picrylhydrazyl (DPPH^•) radical scavenging method, 2,2′-Azinobis(3-Ethylbenzothiazoline-6-Sulfonic Acid) (ABTS^•)⁺ radical activity, and Ferric Reducing Antioxidant Power (FRAP) assay. Several complexes exhibited higher radical scavenging efficiency than quercetin, with inhibition percentages exceeding 80% in the DPPH^• and ABTS^•+ assays. Others showed reduced activity due to the masking of redox-active hydroxyl groups during metal coordination. FRAP results corroborated these trends, indicating metal-dependent modulation of reducing power. Antimicrobial evaluation revealed that selected complexes were more active than free quercetin, particularly against Staphylococcus aureus and Candida spp., with minimum inhibitory concentrations (MICs) ranging from 75–250 μg mL⁻¹. Overall, metal complexation significantly alters the electronic structure and biological behavior of quercetin, highlighting the potential of metal–flavonoid complexes as multifunctional antioxidants and antimicrobials. Full article

Pt-based catalysts remain the most effective materials for the oxygen reduction reaction (ORR) at the cathode of proton exchange membrane fuel cells (PEMFCs); however, platinum scarcity and high cost severely limit the large-scale deployment of the technology. Improving catalytic activity and durability through precise control of nanoparticle morphology is therefore crucial for reducing costs and enhancing sustainability, enabling PEMFC widespread adoption. In this context, carbon-supported Pt-based nanoparticles with a 30 wt.% Pt loading were synthesized by an organometallic chemistry approach using hexadecylamine (HDA) as a stabilizer, allowing fine control over nanoparticle morphology. Two distinct synthesis pathways (one-pot and two-step procedures) were used to prepare platinum catalysts supported on KetjenBlack EC-300J (KB), and their influence on the electrocatalytic activity of the obtained nanomaterials was studied. Furthermore, the effect of HDA stabilization on catalyst performance was investigated. Directly synthesized Pt/KB catalysts exhibited similar ORR mass activity, regardless of whether or not HDA was present. Pt/KB prepared by the two-step procedure showed a significantly lower performance. Additionally, despite a larger loss of electrochemical surface area during an accelerated stress test compared to a commercial Pt/C reference, Pt^HDA/KB and Pt/KB catalysts maintained stable mass activity and limited specific activity degradation, highlighting the beneficial effect of nanoparticle stabilization in the presence of HDA on prolonged electrocatalyst cycling. Full article

A modular synthetic route has been developed to prepare a new series of cationic ruthenium(II) complexes with electron-withdrawing 1,2-diacylcyclopentadienyl ligands. The 2-acyl-6-hydroxyfulvenes were synthesized from cyclopentadienide and acyl chlorides and converted to Tl(I) cyclopentadienyl salts using Tl₂SO₄/KOH. Transmetalation with [Ru(η⁶-p-cymene)(μ-Cl)Cl]₂ followed by PF₆⁻ metathesis gives the complexes [Ru{η⁵-1,2-C₅H₃(CO–R)₂}(η⁶-p-cymene)][PF₆] (R = t-Bu, p-Tol, p-ClC₆H₄, p-IC₆H₄) in moderate to high yields. The new compounds were characterized by NMR and IR spectroscopy; mass spectrometry and elemental analysis were performed where applicable. X-ray analysis of one of the complexes confirms that electron-deficient Cp ligands retain η⁵-coordination and structural planarity within Ru(II)–arene sandwich architectures, highlighting their potential utility in electronically tunable organometallic frameworks. Full article

Titanium alloys are widely used in biomedical applications, especially in dental implants. In this work, individual TiO_xC_y thin films and a novel multilayer coating approach were investigated to prevent early implant failure through surface properties optimization. The research focuses on designing an innovative TiO_xC_y organometallic multilayer coating, varying from mineral (low C) to organic (high C), on Ti6Al4V substrates. These coatings were prepared using the PECVD technique, varying parameters as the reactive gas flow to modify the chemical composition, hydrophilicity, and layer thickness. Comprehensive characterization of the surface was conducted using XPS, and by contact angle to evaluate wettability. To further understand the chemical composition within each layer, XPS depth profiling analyses were performed. The results revealed that the newly designed multilayer coating with a decreasing reactive gas flow clearly exhibited a gradient in its composition. Near the upper substrate surface, the layers display a mineral-like, low-carbon structure, transitioning to an organic-like, high-carbon composition at the outermost surface. Full article

The analysis of intact phosphine ligands and phosphino organometallic complexes by mass spectrometry is problematic due to the reactivity of phosphorous(III) leading to rapid oxidation and decomposition of the ligands and complexes. Traditionally, the preferred ionisation method for this problematic class of analytes is electrospray ionisation. However, electrospray is often performed in protic solvents which can promote oxidation of the analyte, especially for those that are already prone to oxidation. This study presents the application of chip-based nanospray ionisation for the analysis of these classes of analyte. Nanospray operates at significantly reduced voltages compared to electrospray and at room temperature and, most importantly, is compatible with a wider range of solvents—included non-protic solvents like toluene and THF. The success of this methodology is initially demonstrated by analysis of the commercial ligand DPPE and then by analysis of a wide range of synthetic phosphine ligands and phosphino organometallic complexes produced in-house at the School of Chemistry, University of Bristol. In all cases, the resulting mass spectra are dominated by intact molecular species with only a small number of oxidised products being observed. In some cases, cationated ions are also observed along with some minor fragmentation or decomposition of the complexes. Full article