Applied Organometallic Chemistry最新文献

Preserving our environment is essential for sustaining life, yet contaminants like nitrofurantoin—a widely used antibacterial drug—pose significant risks to both ecological and human health. In the quest for a pollution-free environment, the detection of such contaminants is critical. This study focuses on the development of monometallic and bimetallic MOFs, renowned for their properties, like high surface area and tunable characteristics, which make them ideal for electrochemical sensing applications. The preparation involves the hydrothermal synthesis of monometallic and bimetallic organic frameworks with aluminium (Al) and manganese (Mn) metals using 3,5-pyridine dicarboxylic acid (PDC), with successful formation confirmed by XRD, FT-IR, SEM, and XPS. The electrochemical sensing properties of these MOFs are studied by using CV and DPV. Various optimization studies are carried out to detect the optimal MOF, and it is found that AlMn-PDC MOF/GCE shows high electrochemical performance, with the synergistic effect between Al and Mn enhancing the overall activity. Furthermore, real sample analysis confirmed the effectiveness of the sensor by achieving recoveries of 98.3% and 99.5% in milk and tap water, respectively. These findings highlight the potential of the AlMn-PDC MOF/GCE as a highly sensitive and selective tool for nitrofurantoin detection, emphasizing the role of bimetallic MOFs in environmental monitoring applications.

The advancement of visible-light harvesting Pt(II) complexes with extended excited state lifetimes is crucial, as these properties are essential for their applications in photocatalysis, nonlinear optics, photodynamic therapy, among other areas. In this study, we synthesized platinum complexes with main ligands bearing sulfur (S) donor atoms, which not only shifted the absorption into the visible range but also increased the excited state lifetimes in solution as well as in solid state. In this context, two series of platinum complexes (C1a–C6a and C1b–C6b) were synthesized in excellent isolated yields in a single step reaction catalyzed by CuI in the presence of base from precursor complexes (PC1a–PC6a and PC1b–PC6b) bearing chloride ancillary ligand. These complexes were characterized by multiple analytical techniques, among them five complexes (C1a, C5a, C6a, C2b, and C6b) were analyzed in solid state by single crystal X-ray analysis that showed the exact orientation of the ligands around Pt and intramolecular/intermolecular bonding in these complexes. The solid-state structure demonstrated dimeric structures interacting through noncovalent π⋯π stacking that could be responsible for extended lifetime, longer wavelength emission, and phosphorescence. These complexes absorbed mainly around 240 to 260 and 420 to 500-nm visible region assigned to ligand–ligand charge transfer (LLCT) and metal-to-ligand charge transfer (MLCT), respectively. The photoluminescence was observed in 630-nm region when excited at 450-nm visible wavelength in both solution and solid state. The absorption and emission properties of all these complexes were further investigated by time-dependent density functional theory (TD-DFT) calculations that rationalized the effect of different constituents on the main SNO donor ligand. The strong absorption in the visible region and emission in the near-infrared (NIR) region in both solid and solution state suggested that these complexes could have potential applications in various fields of optoelectronics, materials science, and photodynamic therapy.

The g-C₃N₄@SiW₁₁Co catalyst was synthesized through a three-dimensional hollow g-C₃N₄ framework derived from cyanuric acid and melamine, followed by controlled deposition of SiW₁₁Co. The resulting material exhibits a specific surface area of 135 m² g⁻¹ higher than pristine g-C₃N₄ of 82 m² g⁻¹. Under thermocatalytic conditions (atmospheric pressure, 80°C), it achieves > 99% epoxide conversion within 8 h. When irradiated with a 12-W white LED, the catalyst maintains > 99% conversion efficiency over 12 h under the same mild conditions. Notably, the catalyst shows excellent recyclability, retaining > 95% of its initial activity over seven consecutive cycles in both thermocatalytic and photocatalytic modes. Systematic mechanistic studies confirm that the enhanced performance stems from synergistic effects between the 3D hollow g-C₃N₄ support and SiW₁₁Co, which collectively improve charge separation, CO₂ adsorption, and epoxide activation. This dual-functional catalyst represents a significant advance over conventional single-mode systems, offering a versatile platform for efficient CO₂ conversion under mild conditions.

Fischer–Tropsch synthesis (FTS) is a green and sustainable technology that enables the direct conversion of biomass-derived syngas (CO and H₂) into gasoline range fuels. Fe-based bifunctional catalysts have attracted significant attention from researchers owing to their excellent catalytic performance. However, the influence of reaction space regulated by catalyst morphology and crystal growth orientation on FTS catalytic performance remains insufficiently investigated. In this study, two types of hierarchical porous catalysts with distinct morphologies (2D disc-like and 3D cubic-like) were fabricated. The effect of crystal growth orientation on catalytic performance was explored by adjusting the hydrothermal reaction time. In this work, ZSM-24 was physically mixed with 3D cubic-like catalyst and 2D disc-like catalyst, respectively. The corresponding bifunctional catalysts were denoted as FeZ and FedZ. It was found that FeZ-2 and FeZ-10 with a comparable preferred orientation between (104) plane and (110) plane provide an excellent C₅–C₁₁ selectivity of 64.6 and 62.9 wt%. In comparison with the 2D structured FedZ-10 catalyst, the 3D structured FeZ-10 catalyst is more suitable for the transportation of syngas and products during FTS. Thus, the FedZ-10 catalyst only achieves a CO conversion of 43.7%. In contrast, the 3D structured FeZ-10 catalyst with a larger reaction space exhibits a high CO conversion of 93.6% along with excellent selectivity toward the target gasoline range products. This phenomenon is attributed to the fact that the catalyst structure not only affects the transformation of iron oxides into active iron carbides but also determines the mass transfer space for FTS products, thereby influencing the catalytic performance.

Aiming at the problem of partial carboxyl coordination unsaturated in the one-dimensional zinc-organic frameworks recently reported, in this study, novel two-dimensional ones were successfully synthesized by the solvothermal method using triethylamine and acetic acid to synergistically regulate the full deprotonation of ligands and the coordination process of zinc ions. The materials can be used as a heterogeneous catalyst for the condensation reaction of o-phenylenediamines with aldehydes under mild conditions to efficiently synthesize benzimidazoles with a yield of up to 95%. The catalyst exhibited excellent cycle stability; that is, the catalytic activity almost kept untouched during 15 times of continuous use, and PXRD and FTIR confirmed that the structure remained intact.

Photodynamic therapy (PDT) is a candidate approach for cancer treatment. In PDT applications, a fluorescent molecule, called photosensitizer (PS), induces light-directed production of reactive species, resulting in cytotoxicity. Having tunable fluorescence and easy derivatization properties, the BODIPY core is widely used as a PS. To further increase the light-induced toxicity, studies have shown the conjugation of heavy metals to the BODIPY core. However, such complexes are still needed to fully figure out their potential. In the current study, as part of an ongoing one, two novel ruthenium-BODIPY complexes were synthesized and characterized by structural, photophysical, and biological methods. To obtain complex structures between ruthenium dimers and BODIPY units, [RuCl₂(p-cymene)]₂ dimers, and non-iodo and di-iodo BODIPY derivatives were reacted in methanol-tetrahydrofuran (THF) medium. Photophysical properties, fluorescence lifetime, molar extinction coefficient, photostability, and capability of singlet oxygen generation were determined using absorption and/or fluorescence spectroscopy. Besides, the structures of the complexes were further clarified by the single-crystal X-ray technique. The cytotoxicity of compounds was examined against the human cervical cancer cell line, HeLa, and breast cancer cell line, MDA-MB-231, both in the dark and by light irradiation. Accordingly, both precursors and their ruthenium complexes were light-dependent toxic; nevertheless, di-iodinated meso-pyridine-substituted BODIPYs displayed light-independent toxicity by long-term treatments. Moreover, the effects of the complexes were cell-specific and the toxicities of di-iodinated BODIPY complexes were inversely correlated with the concentrations, underlying a possible aggregation and/or unpredicted cellular interaction pattern. These results emphasize that further functionalization and molecular characterization of BODIPY-ruthenium complexes are still required for PDT applications.

The application of titanium dioxide (TiO₂) in photocatalysis is restricted by issues such as its wide band gap, inability to absorb visible light, and easy recombination of photogenerated carriers. To enhance the photocatalytic activity of TiO₂, the formation of an [O_v·Ti³⁺]⁺ impurity level through Ti³⁺-doping is an effective strategy. In this study, a highly efficient photocatalyst Pd/TiO₂-C_Act250, featuring high concentrations of oxygen vacancies and Ti³⁺ level, was successfully synthesized by the initial activation of MIL-125(Ti) at 250°C, followed by wet impregnation with Pd (NO₃)₂ and subsequent pyrolysis. The activation temperatures significantly affected the content of oxygen vacancies and Ti³⁺/Ti⁴⁺ ratios in the catalyst. The activated catalysts Pd/TiO₂-C_Act showed increased oxygen vacancies and Ti³⁺/Ti⁴⁺ ratios, reaching the highest values upon activation at 250°C. The high oxygen vacancy concentration and Ti³⁺/Ti⁴⁺ ratio broadened the light-absorption range and promoted the efficient separation of electron–hole pairs, ultimately resulting in superior photocatalytic performance, with a catalyst in low Pd concentration (0.008 mol%), for the Suzuki–Miyaura reaction.

Four kinds of novel and air-stable N,N-chelated half-sandwich Ir complexes were successfully synthesized by using Schiff base as the ligands, and their general formula was [Cp*IrClL]. These complexes were conveniently prepared in good yields through a straightforward synthetic method. In the amide synthesis reactions, these newly prepared stable complexes demonstrated outstanding catalytic performance. The complexes 1–4 were utilized as catalytic precursors in the amidation reaction between NH₂OH•HCl and aldehydes, as well as in the hydration reaction of nitriles, and a diverse array of amides featuring various functional groups were synthesized via the one-pot method with high selectivity and good yields. This catalytic system offers several advantages, including excellent and diverse catalytic activity, a wide scope of substrates, mild catalytic conditions, and environmentally friendly solvents. Characterization methods of NMR, IR, UV–Vis, single-crystal X-ray diffraction, and elemental analysis were utilized to thoroughly analyze the structure of these synthesized Ir (III) complexes.

The aim of this study was to perform C–H bond activation reactions on aromatic rings using copper-based metal–organic frameworks (Cu-MOFs), ultimately leading to the synthesis of various arylamine derivatives. Initially, the Cu₂(BDC)₂DABCO MOF was synthesized using terephthalic acid and DABCO as organic linkers. The structure and morphology of the synthesized MOF were characterized by FE-SEM, XRD, and FT-IR analyses. Subsequently, a series of N-(2-pyridyl) benzamide derivatives were prepared through a straightforward and efficient method within just 2 h at room temperature using dichloromethane as the solvent. In the final step, N-aniline-N-(2-pyridyl) benzamide derivatives were synthesized via direct C–H bond activation using the bidentate-ligand Cu-MOF catalyst in DMF. This method offers several advantages, including high reaction yields, reduced reaction steps, and shorter overall reaction time, as well as catalyst recyclability and long-term stability. A general scheme of the reaction is illustrated below.

A sustainable approach has been reported for synthesising highly substituted imidazoles via copper(I) catalysed multicomponent cyclocondensation reaction using benzil, aldehyde, aniline and ammonium acetate. The moisture-stable copper(I) containing NNP tridentate complexes of general formula [Cu(I)(PPh₃)(L_1–3)] [HL₁ = (2-(diphenyl phosphaneyl benzylidene hydrazineyl benzo thiazole, HL₂ = diphenyl phosphaneyl benzylidene hydrazineyl quinoline, HL₃ = diphenyl phosphaneyl benzylidene hydrazineyl nicotinic acid] were obtained by reacting [Cu (PPh₃)₂(CH₃COO)] with phosphine functionalized hetero aromatic hydrazone ligands (HL_1–3) in equal moles of each reactant. The establishment of the novel complexes was validated using multiple spectral analyses (FT-IR, UV–VIS, NMR, and ESI-MS). X-ray crystallographic analysis of a single crystal confirms tridentate ligand coordination and a deformed tetrahedral geometry surrounding the metal ion. The novel copper(I) complexes were assessed as catalysts for the production of highly functionalized imidazole compounds using single-step condensation reactions of three or four components. A diverse array of substituted imidazole derivatives was synthesized by an annulation reaction utilizing 1 mol% catalyst loading, achieving a maximum yield of 98%.