ChemistrySelect最新文献

Chlorinated rGO is a promising 2D material with unique properties. A new synthesis method combines chlorine intercalation and graphite sheet surface reduction into a single step. Various tests confirmed the chloride content improves storage capacity. The high chloride content of the material improved the electrolyte's d-spacing and ion mobility, leading to increased storage capacity. Additionally, the potential of chlorinated RGO as an electrode material was examined using a 1 M H₂SO₄ solution as the electrolyte, and various tests including CV, EIS, and GCD were conducted. At a current density of 1 A/g, the chlorinated graphene material exhibited a specific capacitance of 373.4 F/g at a high rate, along with EDL capacitance. It also demonstrated excellent stability over 5000 cycles. These halogenated graphene compounds are highly promising for supercapacitor applications.

As a versatile platform molecule derived from biomass, 5-hydroxymethylfurfural (HMF) has the potential to be transformed into a variety of chemicals. Of these, furan-2,5-dimethylcarboxylate (FDMC) stands out as an excellent precursor for the synthesis of poly(ethylene furandicarboxylate) (PEF), a polymer with broad applications in the production of various polymeric materials. However, a majority of studies have focused on the use of noble metal catalysts to achieve the direct oxidative esterification of HMF for the production of FDMC. Given the scarcity and high cost of noble metal catalysts, there is a pressing need to develop non-noble metal catalysts to efficiently facilitate the direct oxidative esterification of HMF. Accordingly, a bimetallic catalyst, MnO@Co-CN, was prepared in this paper by a simple coprecipitation method, and a 90.3% FDMC yield was obtained under optimal conditions. The findings revealed that in the oxidative esterification of HMF, MnO_x predominantly adsorbs the reactants onto the catalyst surface, whereas CoO_x is primarily responsible for the oxidation. The synergistic interaction between Mn and Co enhances the catalytic performance, leading to the superior oxidative esterification outcomes. This work offers a cost-effective, scalable method for FDMC synthesis, highlighting potential for industrial applications.

The present study deals with the theoretical investigation of mechanistic and regiochemical aspects of the Pd(II)-catalyzed dehydrogenative Heck olefination of selenophenes. The detailed reaction mechanism was established, and the roles of the catalyst and regioselectivity were well rationalized. Our results clearly showed that the whole reaction involves a concerted metalation-deprotonation (CMD) process between the C² site of selenophene and Pd(OAc)₂ in the first catalytic cycle. Afterward, the olefin coordinates to the palladium, followed by a regioselective 1,2-migratory insertion to form a C─C bond. Then, β-hydride elimination would give the final 2-monoolefinated product. Subsequently, the second catalytic cycle generates the symmetrical 2,5-diolefinated selenophene product. Another key finding of this study is that selenophene and its monoolefinated product act as nucleophiles, while the catalyst behaves as an electrophile. A global reactivity index (GRI) analysis revealed that the nucleophilicity (N_k) of C², C³, C⁴, and C⁵ atoms in selenophene plays an important role in controlling the reaction selectivity at these sites. However, the distortion energies play a more important role in controlling the selectivity of reactions at the olefin C sites.

Consisting of organically-modified silica entrapping silver nanoparticles originally derived from methyltriethoxysilane (MTES) and tetraethylorthosilicate (TEOS) only, the SilverSil sol–gel coating shows significant antimicrobial activity (in vitro). Now, we report the outcomes of investigation aimed at developing SilverSil coatings to functionalize textiles. We investigate the use of 3-(aminopropyl)trimethoxysilane (APTMS) to stabilize the SilverSil nanosol precursor and increase the Ag nanoparticle encapsulation efficiency. We further study the effect of selected parameters of the sol–gel polycondensation process in sight of practical application of SilverSil as a low-cost antibacterial coating of broad scope and limited antimicrobial resistance.

This study delved into the interaction between the neurological drug zonisamide (ZNS) and β-cyclodextrin (β-CD) using an innovative coprecipitation technique, leading to the formation of a stable 1:1 supramolecular inclusion complex (IC). Analytical tools, including ¹H NMR, FTIR spectroscopy, ESIMS, UV–vis spectroscopy, and SEM, revealed the structural details of this assembly. Job's plot confirmed the stoichiometric ratio, whereas binding constants were determined through UV–vis spectroscopic titrations using the Benesi–Hildebrand method. ESIMS data corroborated these findings. Molecular modeling and density functional theory (DFT) calculations provided additional evidence of complexation, demonstrating the stability of the IC through adsorption energy analysis. Biological evaluations showed enhanced antioxidant and antimicrobial activities of the ZNS+β-CD complex compared to pure ZNS, reflecting its improved properties. Encapsulation within β-CD significantly increased the solubility of ZNS in aqueous media, enabling lower effective dosages and reducing potential side effects. The study's experimental and computational findings aligned seamlessly, affirming the encapsulation of ZNS within β-CD and advancing our understanding of supramolecular chemistry. This work highlights the potential of β-CD to optimize drug solubility and therapeutic efficiency, offering a promising approach for improved drug delivery systems.

DFT and TD-DFT methodologies were applied to study seven new donor (T1–T7) compounds based on benzodithiophene (BDT) for organic solar cells (OSCs). The newly designed molecules (T1–T7) were computationally analyzed and compared with reference molecules (TR) to investigate their geometrical, photovoltaic, and optoelectronic properties. These analyses included evaluations of the compounds' frontier molecular orbital (FMO), density of state (DOS), electron density distribution pattern, open circuit voltage (V_oc), absorption spectra, charge mobility, and transition density matrices (TDM). In comparison to other structures studied, the optoelectronic properties of the suggested structure T1 in chloroform solvent were the most improved, having a smaller band gap (3.75 eV), a greater maximum absorbance (543 nm), and lower excitation energy (2.28 eV). In comparison to TR, V_oc is high for every constructed molecule which results significant efficiency of organic solar cell. As a result, every computed property strongly supports the potential of our proposed molecules in solar energy applications.

Vepdegestrant (ARV-471) is a novel estrogen receptor (ER) degrader currently under clinical evaluation for the treatment of ER-positive and HER2-negative breast cancer. We have developed an efficient catalytic stereoselective synthetic route to produce this important compound. The key step involves a Ruthenium-catalyzed asymmetric hydrogenation, which establishes the critical stereocenter with exceptional diastereoselectivity(>99% de). This method obviates the need for chiral chromatographic separation, thereby significantly improving the efficiency and scalability of the synthetic sequence compared to previously reported approaches.

We report herein an efficient synthesis of fully Boc-protected, up to 13-meric polymer of 1,3-propanediamine. The synthesis was facilitated by one-pot conversion of (up to six) N-Ns groups to N-Boc groups under conditions of 1) PhSH and Cs₂CO₃ for deprotection of the Ns group, followed by 2) Boc₂O for Boc protection. The average yield per Ns group was extremely high, especially for substrates with four to six Ns groups (94.6%–96.6%).

Nowadays, the sluggish hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) kinetics are the key obstacles limiting the commercial application of water splitting. In this study, a size-matching strategy is proposed to construct the molybdenum-doped CoS₂ polyhedra (Mo-CoS₂) by encapsulating polyoxometalate (POM, H₃PMo₁₂O₄₀) guests into mesoporous zeolite imidazolium framework-67 (ZIF-67), with thioacetamide (TAA) serving as a gentle sulfur source. The catalyst exhibits a pronounced hollow structure due to the synergistic etching effects of POM and TAA, which can increase the number of active sites. Additionally, the incorporation of Mo optimizes the electronic structure, thereby improving both HER and OER performance. In alkaline electrolytes, Mo-CoS₂ delivers an overpotential of 330 mV and 269 mV for OER and HER, respectively, to produce a current density of 100 mA cm⁻². Moreover, Mo-CoS₂ demonstrates exceptional performance in overall water splitting, achieving a cell voltage of 1.55 V at 10 mA cm⁻², along with outstanding long-term stability. This study provides a promising avenue for the structural and component optimization of cobalt sulfide, which could significantly improve the efficiency of hydrogen production.

Pseudouridine (Ψ) is one of the most common post-transcriptional modifications in RNA and has been known to play a significant role in several crucial biological processes. The N1-methyl derivative of pseudouridine, that is, N1-methylpseudouridine has also been reported to be important for the stability and function of RNA. The critical contribution of N1-methylpseudouridine in the efficiency of the COVID-19 mRNA vaccines requires a better understanding of the role of these modifications in the structure, stability, and function of RNA. We have previously studied the structural and thermodynamic properties of RNA duplexes with an internal Ψ-A pair and reported the stabilizing effect of Ψ over U. In the present study, we have extended our work to understand the properties of RNA duplexes with an internal m¹Ψ-A pair. Additionally, we theoretically demonstrate the effect of substituting internal U-G, U-U, and U-C mismatches with the Ψ-G, Ψ-U, and Ψ-C mismatches and also with the m¹Ψ-G, m¹Ψ-U, and m¹Ψ-C mismatches, respectively, within dsRNA. Our results indicate the context-dependent stabilization of base stacking interactions by N1-methylpseudouridine compared to uridine and pseudouridine, presumably resulting from the increased molecular polarizability due to the presence of the methyl group.