Applied Organometallic Chemistry最新文献

Reactions of ligand pyrazine-2-carboxylic acid (HL1) with [Ru(η⁶-p-cymene)Cl₂]₂ precursor gave the dinuclear piano-stool ruthenium (II) complex [{Ru(η⁶-p-cymene)Cl₂}-μ-(L1)-{Ru(p-cymene)Cl}] (Ru1). Separately, reactions of N-(quinolin-8-yl) pyrazine-2-carboxamide (HL2), 5-methyl-N-(−(quinolin-8-yl) pyridine-2-carboxamide (HL3) and 5-chloro-N-(quinolin-8-yl) pyridine-2-carboxamide (HL4) with [Ru(η⁶-p-cymene)Cl₂]₂ dimer in the presence of KPF₆ afforded the cationic dinuclear complexes [{Ru(η⁶-p-cymene)Cl}₂-μ-(L2)][PF₆] (Ru2), [{Ru(η⁶-p-cymene)Cl}₂-μ-(L3)][Ru(L3)Cl₃] (Ru3) and [{Ru(η⁶-p-cymene)Cl}₂-μ-(L4)][PF₆] (Ru4). The Ru (II) complexes were analysed using FT-IR, ¹H, ¹³C{¹H}, ³¹P{¹H} (Ru2 and Ru4) and ¹⁹F (Ru2 and Ru4) NMR spectroscopic techniques, micro-analyses and mass spectrometry. Molecular structures of complexes Ru1 and Ru3 were confirmed to display piano-stool coordination nature using single-crystal X-ray crystallography analyses. All the complexes (Ru1–Ru4) mediated the transfer hydrogenation (TH) of a broad spectrum of ketones in isopropanol in the presence of a base and demonstrated high catalytic activities (TON of 24,000) at catalyst concentrations of 0.002 mol%. In general, the catalytic performance of these Ru (II) complexes depended on the identity of the ligands, coordination chemistry and ketone substrates.

In this work, novel Ni (II) complexes, namely, [Ni₂(L)₂(OAc)₂(EtOH)₂] (1a), [Ni₂(L)₂(OAc)₂(H₂O)₂] (1b-1) and [Ni₂(L)₂(OAc)₂(EtOH)₂] (1b-2) as co-crystal were synthesized by the 1:1 condensation (https://www.sciencedirect.com/topics/chemistry/condensation) of Ni (CH₃COO)₂·4H₂O and Schiff base ligand (H₂L) (2-hydroxy-4-methoxybenzaldehyde and 2-amino-2-methylpropanol). The ligand based on Schiff base and fabricated complexes (1a) and (1b-1 and 1b-2) were successfully identified by CHN assessment, FT-IR, UV–Vis spectra, melting point and CV voltammogram. The electrochemical behavior investigation shows that the nickel complexes exhibited irreversible oxidation processes in methanol solution. Additionally, the crystal structures of complexes (1a) and (1b) have been recognized by single-crystal X-ray diffraction investigation. It turned out that the complexes (1b-1) and (1b-2) crystallize together, making a co-crystal 1b with an additional EtOH solvent molecule in the crystal structure. A detailed study of intermolecular exchanges was performed using attractive graphical analysis tools such as three-dimensional Hirshfeld surfaces analysis, two-dimensional fingerprint plots (FPs), and enrichment ratios (E), which make C-H … C, C-H … O hydrogen bond, C … O, H … H, and O … O short contacts on Hirshfeld surfaces with color code are observed. Moreover, an appraisement of the inhibitory trace against coronavirus (main protease SARS-CoV-2, PDB ID: 6Y2F) and molecular targets of human angiotensin-converting enzyme-2 (ACE-2) was performed by a molecular docking study in which two nickel complexes performed best for PDB protein ID: 6M0J and all three complexes for PDB protein ID: 6Y2F.

Three hydroxyl functionalized crystalline K-doped g-C₃N₄ were synthesized from dicyandiamide, melamine, ammonium chloride, ammonium oxalate, and ammonium citrate via ionothermal polycondensation using KCl as molten salt under N₂ atmosphere, which served as efficient recyclable photocatalysis realized that generating H₂O₂ directly from seawater with air by 2e⁻ ORR pathway under stimulated solar irradiation in ambient conditions. Under optimized conditions, the highest H₂O₂ production rate of 1622 μmol g⁻¹ h⁻¹ for duration of 10 h was obtained. The cycling performances of HPCN-2 displayed reusable for five times without noticeably loss of its catalytic activity. This work presents a real safer, sustainable, and economical approach for production of H₂O₂ directly from abundant natural seawater.

In this work, the effect of different parameters on catalyst efficiency in the catalytic oxidative desulfurization (ODS) and denitrogenation (ODN) process is studied. A series of samples with different metal compounds, including Ni, Cu, Co, CoNi, CoCu, and CuNi on a reduced graphene oxide (GO) were prepared by an impregnation method. The synthesized samples were carefully characterized by Fourier transform infrared (FTIR), field emission scanning electron microscopy (FESEM), X-ray photoelectron spectroscopy (XPS), Brunauer–Emmett–Teller (BET) analysis, and X-ray powder diffraction (XRD) techniques. The potential of this methodology was illustrated by the oxidation of 84.11% carbazole (CBZ) and 88.36% dibenzothiophene (DBT) in model fuel containing 500 ppmw sulfur and nitrogen. The effect of DBT and CBZ initial concentration and oxidant type on the oxidation process was investigated. The initial concentration of 250 ppmw for DBT and 100 ppmw for CBZ showed more efficiency than other initial concentrations (1,000, 750, 500, 250 ppmw) for DBT and (500, 400, 250, 100 ppmw) for CBZ, and NaClO as an oxidant showed higher performance than H₂O₂, formic acid, and oxygen. The results indicated that the Co-Cu/rGO catalyst shows higher activity than other prepared catalysts in the oxidation of DBT and CBZ. Moreover, the catalyst could be regenerated three times with no discernible decrease in its catalytic activity. Lastly, the catalytic oxidation of CBZ and DBT was the proposed reaction mechanism.

Porphyrin-based porous organic polymers (Por-POPs) are attracting increasing attention because of their potential in visible light photocatalysis. The distinctive attributes of Por-POPs have been elucidated by investigating their response to specific reactions, such as the aerobic oxidation of sulfides. However, most researchers choose porphyrin molecules with relatively short peripheral substituent chains and strong stiffness to construct porphyrin-based materials, especially Por-POPS. Herein, we designed and prepared a flexible POP material H₂Pp-TAPM by incorporating extra π-conjugated rigid units TAPM into a relatively flexible porphyrin monomer H₂Pp through imine linkages. The POP synthesized in this study has demonstrated the ability to facilitate the transfer and dissociation of photogenerated electron–hole pairs, leading to the production of singlet oxygen ¹O₂ and superoxide radical anions O₂˙⁻. These anions act as effective mediators for the selective aerobic oxidation of sulfides, resulting in the conversion of 99% and the selectivity more than 99%. Furthermore, the H₂Pp-TAPM has excellent stability and recyclability, indicating its attractiveness as heterogeneous photocatalyst for the transformation of organic compounds. This makes it a promising candidate for visible-light-driven reactions.

In this study, nPd/Fes were dispersed on peanut shells-derived alkali-modified biochar (BC_alk) to obtain BC_alk-nPd/Fe composite for overcoming the instability, agglomeration, and oxidation of nPd/Fes. Results demonstrated that the dispersion stability and thermal stability of nPd/Fes were improved and the surface passivation layer was thinned by nanoparticles loading onto the alkalized biochar. Characterization analyses revealed of the improved 2,4-D dichlorination by BC_alk-nPd/Fe. After biochar alkalization, more Si-O-Si sites on BC_alk responsible for supporting nZVI particles were formed and coupled with nZVI to generate Si-O-Fe. Hence, nPd/Fes were immobilized on BC_alk, while the increased oxygen-containing surface functional groups promoted electron transport between nPd/Fes and 2,4-D. Therefore, the BC_alk-nPd/Fe exhibited higher dechlorination efficiency toward 2,4-D than that of nPd/Fe and BC_raw-nPd/Fe. About 99.25% and 89.11% of the 2,4-D removal and dechlorination, respectively, were achieved after 150 min. Kinetic studies revealed that the removal of 2,4-D using nPd/Fe, BC_raw-nPd/Fe, and BC_alk-nPd/Fe fitted well in the Langmuir–Hinshelwood kinetic model, and the order of rate constants was as follows: BC_alk-nPd/Fe > BC_raw-nPd/Fe > nPd/Fe. This study suggested that the prepared composites promoted detoxification and harmlessness of 2,4-D contaminated wastewater and exhibited promising prospect in the efficient treatment of wastewater containing chlorinated organics.

Three GUBZCu, GUBZVO, and GUBZPd chelates have been prepared from 2-guanidino benzimidazole (GUBZ ligand) by a bidentate coordinating approach. FT-IR, mass, and NMR spectra; magnetic moment; CHN analysis; UV–Vis spectra; molar conductance; and TGA were studied to describe and estimate the molecular formulae of tested molecules. The stability constant for GUBZ complexes was estimated in the solution. Also, the pH profile displays the extra stability of tested complexes. Structure elucidation of the studied complexes had been supported by density functional theory (DFT) along with calculated electronic and vibrational spectra. Electronic absorption spectra were estimated practically through UV–Vis spectra and theoretically performed using the time-dependent TD-DFT/B3LYP, for computing the absorption maximum, oscillator strength, and excitation energy of the tested compounds. This study was done into these chelates' catalytic performances for the environmentally friendly synthesis of 7-amino-4,5-dihydro-tetrazolo[1,5-a]pyrimidine-6-carbonitrile derivatives utilizing aromatic aldehyde, malononitrile, and 5-amino tetrazole as reactants. The used reactions have been directed in a concerned environment through a green solvent. The obtained results verified the promising catalytic activity and selectivity of the tested complexes. All tested reaction conditions have been enhanced between variable Lewis acid catalysts in associating to our studied complexes. GUBZPd catalyst presented an advantage in overall tests through high yield, green conditions, and short time. Also, the regaining of hetero-catalyst has prospered as well as recycled through the same effectiveness up to four or five times, and then the performance has been reduced. The mechanism of action has been recommended depending on the capability of the Pd (II) complex for totaling extra bonds above the z-axis as well as reinforced with theoretical study. This strategy's simplicity, safety, commercially accessible catalyst, stability, fast reaction time, and outstanding yields may be used in the industry in the future.

The improvement of high-Z-based metallic nanostructures as radiosensitizers with high monolithicity and versatility by superadditive therapeutic track and the good protective effect is considerable, but they are limited by some problems such as nonideal selectivity for the target tissue. In this study, nanosystems were developed to enhance the efficacy of radiotherapy and reduce cancer cell survival based on innovative gold (Au) functionalized oxygen-single-walled carbon nanotubes (O-SWCNTs). We illustrate the use of folic acid (FA) as a targeting agent and bovine serum albumin (BSA) to stabilize the physiological environment and increase durability. The physical and chemical properties of the nanosystems were evaluated using transmission electron microscopy (TEM), selected area electron diffraction (SAED), dynamic light scattering (DLS), zeta potential, X-ray diffraction (XRD), ultraviolet–visible (UV–Visible), and Fourier transform infrared (FTIR) techniques. Finally, the MTT assay was used to investigate the therapeutic effects of nanoparticles in the 4 T1 mouse breast cancer model in the presence and absence of X-rays. So, the cancer cells experienced a more effective reduction in survival after receiving O-SWCNTs-Au-BSA-FA + 8 Gy than O-SWCNTs-BSA, Au-BSA-FA, and O-SWCNTs-Au-BSA + 8 Gy groups.

Lead halide-based salts exhibit good photoelectric properties; however, the use, leakage, and recovery of toxic lead require careful consideration. Therefore, developing a lead-free optoelectronic material conveniently and quickly is very important. Moreover, there is relatively little research on the salts of bismuth halides. In this study, we synthesized [PEA]₃[Bi₂I₉] single crystals (SC) by volatilizing N,N-dimethylformamide (DMF) solvent at 70°C. The crystal system and spatial group of [PEA]₃[Bi₂I₉] are monoclinic and P2₁/n, respectively. The Tauc plot reveals the optical band gap of the [PEA]₃[Bi₂I₉] SC at 2.048 eV. The carrier mobility of [PEA]₃[Bi₂I₉] SC is 47.4 cm² V⁻¹ s⁻¹. Steady-state fluorescence and time-resolved fluorescence spectrum indicate that there are four fluorescence peaks and about 7 μs lifetime, respectively. The photodetector based on [PEA]₃[Bi₂I₉] SC under different voltages (0.5, 1, 1.5, 2, and 2.5 V) exhibits stability and regularity with turning-on/off of the light. In addition, thermogravimetric analysis (TGA) tests indicate that [PEA]₃[Bi₂I₉] SC has considerable thermal stability at temperatures up to 260°C, showing promise for becoming a high temperature resistant and nontoxic sensor with good application prospects.

Cancer is one of the diseases with the highest mortality rate worldwide. Although PDT has recently produced encouraging outcomes, there are still many areas that need to be improved. The first of these is the negative consequences faced by patients treated with the PDT method when exposed to sunlight. For this reason, a new PDT method has been developed in recent years, and it is aimed at using photosensitizer molecules that can be active in acidic conditions. Since the pH values of tumor tissues are more acidic than normal tissues, preparing molecules that act effectively in acidic conditions will allow for more effective results in treating cancer with PDT. In this context, within the scope of this study, 3-(4-propionylphenoxy)phthalonitrile (1) and its non-peripheral tetra-substituted phthalocyanine derivatives [(2), (3), and (4)] were prepared. With these phthalocyanine derivatives, the novel compounds (5), (6), and (7) were synthesized for the first time. The aggregation tendencies of newly synthesized phthalocyanines (5–7) were investigated in solvent media. The effects of pH changes upon UV–Vis and fluorescence spectra were performed. The electronic and emission spectra of synthesized phthalocyanine derivatives are highly sensitive to pH changes. Formation constant (LogK) values of mono- and di-protonated phthalocyanine forms were calculated by the Henderson–Hasselback equation. The mono- and di-protonated species' equilibrium constants (logK₁ and logK₂) were calculated as ~5.0. This value may be promising for pH-sensitizing photosensitizers. Also, the photophysical and photochemical properties of synthesized metallophthalocyanine derivatives (2) and (5) were studied at different pH values. The singlet oxygen quantum yield of (2) and (5) was calculated to be 0.78 and 0.81 in DMSO, respectively. When pH = 6.4, that is, tumor-pH-values, this value for (5) has increased to 0.92. The newly synthesized phthalocyanines are suitable photosensitizers for PDT applications, especially with high singlet oxygen quantum yield at pH 6.4.