jablonkagroup/rise_ai_scientists huggingface dataset:
Authors: Pranav Kumar | Aleš Růžička | Tomáš Hodík
Source: ChemRxiv (article, 2025-08-31)
Field: Materials Science — Materials Chemistry

WITHDRAWN We report the first enantioselective organocatalysis driven exclusively by chalcogen bonding. A new class of chiral chalcogen-bond donors promotes the asymmetric aza-Henry reaction, governed solely by σ-hole interactions, to deliver drug-relevant β-nitroamines in high yields and enantioselectivities of up to 99:1 er. Mechanistic studies and controlled experiments corroborate the essential role of σ-hole directionality during the enantioselective nucleophilic addition. Despite their perceived weakness, σ-hole interactions proved sufficiently strong to enable substrate binding in competition with the triflate anion bound in the catalyst’s σ-hole. Until now, chalcogen bonding has served only as a supporting interaction alongside more prominent stereodetermining tools; however, this work pioneers its use as an independent stereodetermining tool in asymmetric synthesis, offering a conceptual alternative to traditional hydrogen-bonding or metal-based strategies. Chalcogen ; Enantioselective synthesis ; Catalysis ; Materials science ; Chemistry ; Nanotechnology ; Crystallography ; Organic chemistry Machine Learning in Materials Science ; Chemical Synthesis and Analysis ; Surface Chemistry and Catalysis
Authors: Germán P. Benedictto | Lucas Mardones | María S. Legnoverde | Elena I. Basaldella
Source: Biofuels Bioproducts and Biorefining (article, 2025-02-05)
Field: Materials Science — Materials Chemistry

Transesterification of sunflower oil using catalysts obtained from the dispersion of potassium and calcium salts in mesoporous silica matrices Abstract A set of catalysts was synthesized by impregnating mesoporous silicas (SBA‐15 and MCF) with calcium and potassium salts. The solids obtained were characterized by Fourier transform infrared, scanning electron microscopy, N 2 adsorption/desorption porosimetry, energy dispersive X‐ray analysis and X‐ray diffraction. These catalysts were assessed for the transesterification of sunflower oil into fatty acid methyl esters. The catalyst support and the solids containing calcium exhibited low activity under the mild conditions chosen for this study (65°C and self‐generated pressure). In contrast, the presence of potassium significantly enhanced transesterification at very short reaction times, irrespective of the support nature. The methyl ester content was found to be strongly influenced by the basicity of the catalysts, attributed to different potassium compounds, achieving conversions exceeding 98%. However, catalytic activity declined upon reuse, with only a 5% methyl ester content achieved in the second cycle. This confirmed the hypothesis that metal species leach into the reaction mixture with a mechanism similar to that of homogeneous ones. Transesterification ; Potassium ; Mesoporous silica ; Sunflower oil ; Dispersion (optics) ; Catalysis ; Mesoporous material ; Calcium ; Sunflower ; Chemical engineering ; Chemistry ; Biofuel ; Materials science ; Organic chemistry ; Waste management ; Agronomy ; Food science Mesoporous Materials and Catalysis ; Catalysis and Hydrodesulfurization Studies ; Biodiesel Production and Applications
Authors: Bouamer Amirouche
Source: Journal of Research Updates in Polymer Science (article, 2025-08-03)
Field: Materials Science — Polymers and Plastics

Structural, Magnetic, and Optical Properties of Iron-Doped Polyvinyl Alcohol (PVA) Films for Electromagnetic Shielding and Sensor Applications Pure PVA and Fe-doped composite films were synthesized using the solution casting method in the present work. Doping with iron (Fe) microparticles at weight percentages of 2% and 6%. The morphological, structural, magnetic, and optical properties of the films were investigated using X-ray diffraction (XRD), vibrating sample magnetometry (VSM), and attenuated total reflection (ATR) spectroscopy. XRD analysis revealed that the crystallite size of the iron microparticles, calculated using the Scherrer equation, was approximately 65.5 nm. Magnetic measurements showed a significant enhancement in saturation magnetization (Ms) from 1.6 x10-2 emu/g (2 wt% Fe) to 8.1x 10-2 emu/g (6 wt% Fe), along with increases in coercivity magnetization. The findings indicate that incorporating iron (Fe) particles into the PVA matrix created a new composite material with typical magnetic behavior. The observations demonstrate the material's potentiality towards sophisticated functional uses, such as sensors, electromagnetic shielding, and specialized electronic devices. Polyvinyl alcohol ; Materials science ; Electromagnetic shielding ; Doping ; Composite material ; Optoelectronics Polymer Nanocomposite Synthesis and Irradiation ; Polymer Nanocomposites and Properties ; Electromagnetic wave absorption materials
Authors: Futong Cui | Dong‐Dong Liang | Xiangfei Kong | Dong‐Liang Mo
Source: Advanced Synthesis & Catalysis (article, 2025-12-09)
Field: Chemistry — Organic Chemistry

Synthesis of Imidazo‐Fuzed Pyrazino[2,1‐ <i>b</i> ]quinazolinones Through Gold(I)‐ and Base‐Promoted Intramolecular Hydroamination Cyclization We describe a facile method to prepare a variety of imidazo‐fuzed pyrazino[2,1‐ b ]quinazolinone scaffolds in good to excellent yields through gold(I)‐catalyzed and base‐mediated intramolecular hydroamination reactions of N3‐alkynyl quinazolinone tethered imidazoles. It was found that 5‐methylene imidazo‐fuzed pyrazino[2,1‐ b ]quinazolinones were obtained under gold(I)‐catalyzed conditions, while base‐mediated conditions afforded 5‐alkyl imidazo‐fuzed pyrazino[2,1‐ b ]quinazolinones. The reaction could be easily prepared on a gram scales. More importantly, the prepared 5‐methylene imidazo‐fuzed pyrazino[2,1‐ b ]quinazolinones could be applied in the various metal ions recognition based on their fluorescence properties. Hydroamination ; Intramolecular force ; Quinazolinone ; Sonogashira coupling ; Fluorescence ; Metal ions in aqueous solution ; Reaction conditions Catalytic C–H Functionalization Methods ; Quinazolinone synthesis and applications ; Catalytic Alkyne Reactions
Authors: Federico Belnome | Péter Pál Fehér | András Stirling | Csongor Németh | Tamás Hergert | György M. Keserű | Péter Ábrányi‐Balogh
Source: ChemRxiv (preprint, 2025-06-29)
Field: Chemistry — Organic Chemistry

Versatile Palladium-catalysed C-H Arylation of Fluoroarenes with 2-Chloropyridine Derivatives In this study, we present an efficient protocol for synthesizing 2-(fluorinated aryl)pyridines via direct C-H arylation of fluoroarenes with 2-chloropyridine derivatives. The synthesis of these moieties is typically challenging, often requiring multiple transition metals (Pd, Zn, Ni) and unstable or scarce aryl boronic acids, which limits access to a broad variety of these compounds. The developed methodology employs i-PrOAc as a green reaction medium, exhibits excellent functional group tolerance with minimized catalyst loading, and generates only KCl as the main by-product. Substrate scope studies revealed key substituent effects on both the pyridine and fluoroarene partners, enabling the efficient synthesis of a diverse library of 2-(fluorinated aryl)pyridines. Mechanistic investigations supported by DFT computa-tions provided insights into the catalytic cycle, rationalizing observed trends in reactivity and chemoselectivity. This research advances sustainable and practical methodologies for the synthesis of complex fluorinated aromatic com-pounds with potential applications in materials science, agrochemistry and medicinal chemistry. Palladium ; Chemistry ; Combinatorial chemistry ; Catalysis ; Organic chemistry Catalytic C–H Functionalization Methods ; Fluorine in Organic Chemistry
Authors: Federico Belnome | Péter Pál Fehér | András Stirling | Csongor Németh | Tamás Hergert | György M. Keserű | Péter Ábrányi‐Balogh
Source: ChemRxiv (preprint, 2025-05-26)
Field: Chemistry — Organic Chemistry

Versatile Palladium-catalysed C-H Arylation of Fluoroarenes with 2-Chloropyridine Derivatives: An Experimental and Mechanistic Study In this study, we present an efficient protocol for synthesizing 2-(fluorinated aryl)pyridines via direct C-H arylation of fluoroarenes with 2-chloropyridine derivatives. The synthesis of these moieties is typically a challenging trans-formation, often requiring multiple transition metals (Pd, Zn, Ni) and, at times, unstable or expensive aryl boronic acids. As a result, access to a wide variety of these com-pounds is limited. This method offers a stream-lined, cost-effective alternative to traditional cross-coupling reactions by eliminating the need for pre-functionalization. Its broad functional group tolerance across various substituted pyri-dines and fluoroarenes facilitates the efficient synthesis of a diverse library of 2-(fluorinated aryl)pyridines and enabled late-stage functionalization. The conditions were tested and optimized across various substrates, offering valuable insights into the influence of substituents on coupling efficiency. Using DFT computations, we explored the mechanistic basis of the experimental observations, providing a clear overview of the catalytic cycle, unveiling interest-ing aspects for future optimization. This research advances sustainable and practical methodologies for synthesizing com-plex fluorinated aromatic compounds with potential applications in materials science, agrochemistry and medicinal chemistry. Palladium ; Chemistry ; Combinatorial chemistry ; Stereochemistry ; Catalysis ; Organic chemistry Catalytic C–H Functionalization Methods ; Fluorine in Organic Chemistry
Authors: Arthur R. Zabirov | Д. В. Серебренников | Р. З. Куватова | N. A. Filippova | R. A. Zilberg | О. С. Травкина | М. Р. Аглиуллин
Source: Gels (article, 2025-04-17)
Field: Chemistry — Inorganic Chemistry

Regulation of the Properties of the Hierarchical Porous Structure of Alumophosphate Molecular Sieves AEL by Reaction Gels Prepared with Different Templates Microporous alumophosphate molecular sieves AlPO<sub>4</sub>-n are promising materials for use in catalysis, gas adsorption, and gas separation. However, AlPO<sub>4</sub>-n faces problems such as diffusion limitations that lead to a deterioration in mass transfer. To solve this problem, we studied the crystallization of alumophosphate reaction gels prepared using aluminum isopropoxide and various secondary amines as templates, including diethyl-, di-n-propyl-, diisopropyl-, and di-n-butylamines. Using X-ray diffraction, Ramon spectroscopy, and STEM methods, it has been demonstrated that the reaction gels prepared using DPA, DIPA, and DBA are amorphous xerogels consisting of 5-10 nm nanoparticles. The reaction gel prepared with DEA is a combination of a layered phase and an amorphous aluminophosphate. It has been shown that the use of aluminum iso-propoxide allows the production of AlPO<sub>4</sub>-11 in the form of 2-4 µm aggregates consisting of primary AlPO<sub>4</sub>-11 nanocrystals. The template was found to exert a significant effect upon both the characteristics of the porous structure and the size of AlPO-11 nanocrystals. A template is proposed for the synthesis of hierarchical AlPO<sub>4</sub>-11 with a maximum volume of mesopores. The morphology and crystal size of AlPO<sub>4</sub>-11 were found to strongly influence its adsorption properties in the adsorption of octane. Mesoporous material ; Molecular sieve ; Microporous material ; Chemical engineering ; Materials science ; Template ; Amorphous solid ; Crystallization ; Catalysis ; Porosity ; Nanocrystal ; Adsorption ; Nanotechnology ; Chemistry ; Organic chemistry Zeolite Catalysis and Synthesis ; Mesoporous Materials and Catalysis ; Chemical Synthesis and Characterization
Authors: Mustapha Isah | Fatima Ibrahim Jumare | Hizbullahi Muhammad Usman | Abdulrahman Sani Aliero | Shafi’u Abdullahi Namadi
Source: Journal of Biochemicals and Phytomedicine (article, 2025-09-30)
Field: Materials Science — Materials Chemistry

Navigating The Duality of Silver Nanocomposites: Antimicrobial Promise Versus Cytotoxic Risks Silver nanocomposites (Ag-NCs) have garnered significant attention in recent years owing to their exceptional antimicrobial properties, which make them promising candidates for various biomedical applications. However, concerns regarding their potential toxicity and cellular compatibility persist. This review offers a comprehensive overview of the current status of Ag-NCs, covering their synthesis, characterization, and biological interactions. It examines the effects of Ag-NCs on cellular responses, including cytotoxicity, genotoxicity, and oxidative stress, alongside their potential applications in healthcare systems. The review also underscores the key factors influencing cellular compatibility, such as the size, shape, concentration, and surface chemistry of Ag-NCs. Furthermore, it identifies existing knowledge gaps and suggests future research directions to facilitate the safe and effective utilization of Ag-NCs in biomedical contexts. The literature search was performed using Google Scholar, Web of Science (WoS), and Scopus-indexed repositories. The objective of this review was to advance a comprehensive understanding of the complex interplay between Ag-NCs and biological systems, thereby supporting the development of Ag-NC-based biomaterials with optimal cellular compatibility. Antimicrobial ; Web of science ; Human health Nanoparticles: synthesis and applications ; Graphene and Nanomaterials Applications ; Gold and Silver Nanoparticles Synthesis and Applications
Authors: Regina Petkes | Róbert Tőtős | Judith‐Hajnal Bartha‐Vari | Réka Barabás
Source: Nano Select (article, 2025-09-11)
Field: Materials Science — Biomaterials

Novel Preparation Method for Optimized Doxycycline‐Loaded Polycaprolactone Nanofibers ABSTRACT Nanomaterials can be used for targeted drug delivery, enhanced medical imaging, or cancer treatment. Electrospinning enables the creation of drug‐loaded nanofibers, facilitating sustained release and targeted delivery. A key challenge in developing drug‐loaded electrospun materials is achieving simultaneous solubilization of the polymer and the active ingredient. This study introduces a novel approach for obtaining polycaprolactone‐based nanofibers incorporating doxycycline. Doxycycline is a broad‐spectrum antibiotic, effective against a wide range of infections. Polycaprolactone is a biodegradable polyester known for its slow degradation rate, good mechanical strength, and excellent biocompatibility, making it suitable for biomedical applications. The optimal solvent mixture, enabling the simultaneous solubilization of polycaprolactone and doxycycline, is identified. The fiber diameter in drug‐loaded electrospun materials directly impacts drug release, bioavailability, and therapeutic effectiveness. Key electrospinning parameters, such as applied voltage, flow rate, and tip‐to‐collector distance, govern fiber size, influencing drug delivery efficiency. In this study, a design of experiments framework is utilized to determine the optimal electrospinning parameters. Depending on the specific application, these parameters can be adjusted to achieve the desired fiber diameter, ensuring suitability for the intended use. This study provides valuable insights into optimizing electrospinning parameters, ensuring efficient drug delivery, and advancing biomedical applications. Electrospinning ; Polycaprolactone ; Nanofiber ; Drug delivery ; Polyester ; Fiber Electrospun Nanofibers in Biomedical Applications ; Advanced Sensor and Energy Harvesting Materials ; Tissue Engineering and Regenerative Medicine
Authors: Pinki Yadav | Harsur Jajda | Krunal Modi | H. D. Bhimani
Source: International Journal of Advanced Biochemistry Research (article, 2025-01-01)
Field: Materials Science — Materials Chemistry

Green synthesis of silver nanoparticles from medicinal plant extracts: Applications in antibacterial, antifungal, and biomedical fields In recent years, the development of sustainable and efficient green chemistry methodologies for the synthesis of metal nanoparticles has become a significant area of research. A major objective in this field is to establish eco-friendly approaches for the controlled production of well-characterized nanoparticles. Among various biosynthetic strategies, the utilization of biological organisms has garnered substantial attention, with plants being recognized as highly suitable candidates for large-scale nanoparticle biosynthesis. Nanoparticles synthesized via plant-mediated processes exhibit enhanced stability and a higher synthesis rate compared to those produced by microorganisms. Furthermore, plant-derived nanoparticles display a broader range of morphological variations in terms of shape and size, offering greater versatility for diverse applications. The inherent advantages of plant-based nanoparticle synthesis have prompted extensive investigations into the underlying biochemical and molecular mechanisms governing metal ion uptake, bioreduction, and nanoparticle formation within plant systems. Antifungal ; Silver nanoparticle ; Nanotechnology ; Traditional medicine ; Nanoparticle ; Chemistry ; Materials science ; Biology ; Microbiology ; Medicine Nanoparticles: synthesis and applications
Authors: Negar Noroozi | Hossein Roohi
Source: Research Square (preprint, 2025-09-15)
Field: Chemistry — Physical and Theoretical Chemistry

Substituent and State-Specific Solvent Influences on Novel NIR-Emitting ESIPT-Active Push–Pull Fluorescent Dyes Exhibiting Large Stokes Shifts Cyanine ; Fluorescence ; Stokes shift ; Substituent ; Solvent ; Absorption (acoustics) ; Wavelength ; Molecule Photochemistry and Electron Transfer Studies ; Lanthanide and Transition Metal Complexes
Authors: Pricilla Matseketsa | Tendai Gadzikwa
Source:  (preprint, 2025-01-16)
Field: Chemistry — Inorganic Chemistry

Systematic Pore Hydrophobization to Enhance the Efficiency of an Amine-Based MOF Catalyst We systematically hydrophobicized an amine-based metal-organic framework (MOF) catalyst and applied the functionalized MOFs to the Knoevenagel condensation reaction. A well-defined MOF material composed of both amine- and hydroxyl-bearing linkers was reacted with a series of aliphatic isocyanates (isopropyl, tert -butyl, n -hexyl, and tetradecyl) and, incongruously, was found to preferentially react at the hydroxyl groups. This selective functionalization yielded MOFs in which the catalytically active amines are confined within highly hydrophobic pores, reminiscent of many enzyme active sites. We determined that systematically increasing the hydrophobicity of the pores results in a commensurate increase of catalyst efficiency. Amine gas treating ; Catalysis ; Chemical engineering ; Materials science ; Nanotechnology ; Chemistry ; Engineering ; Organic chemistry Metal-Organic Frameworks: Synthesis and Applications ; Catalytic Processes in Materials Science ; Catalysis and Hydrodesulfurization Studies
Authors: Tarika Thapa Chari
Source: Oxford Journal of Student Scholarship (article, 2025-11-17)
Field: Chemistry — Inorganic Chemistry

Unravelling Cytotoxicity Profile Differences in Structurally Similar Metal-Organic Frameworks Cytotoxicity ; DNA ; Cell culture ; Context (archaeology) Metal-Organic Frameworks: Synthesis and Applications ; X-ray Diffraction in Crystallography ; Metal complexes synthesis and properties
Authors: Amira Ben Gouider Trabelsi | F. V. Kusmartsev | Fatemah H. Alkallas | Asmaa M. Elsayed | Mohamed Rabia
Source: Scientific Reports (article, 2025-11-29)
Field: Materials Science — Materials Chemistry

Tunable optoelectronic properties of reduced graphene oxide superlattices intercalated with poly(2-amino-1-mercaptobenzene) for Van der Waals photonic heterostructures We have discovered a novel class of van der Waals (vdW) materials composed of reduced graphene oxide (rGO) superlattices that can be intercalated with various polymeric compounds. The bandgap in these groundbreaking graphene oxide-derived materials can be modulated and set by altering the reduced oxygen concentration and varying the intercalating agent's quantity. As such, these vdW materials could possess superior electro-optical features and a broader scope of applications than traditional graphene. For clarity on this concept, we outline the synthesis of these materials. We have successfully produced them and confirmed their exceptional optoelectronic characteristics through measurement. For instance, we intercalated highly ordered layers of rGO using poly-2-amino-1-mercaptobenzene (P2AMB) as an exemplary case. The resulting novel vdW material demonstrated extraordinary optical broadband absorbance up to 690 nm due to its fine crystalline size of 16 nm and a small bandgap of 1.86 eV, which is further tunable by decreasing the oxygen concentration in the graphene oxide sheets. We tested this vdW thin film as a light-capturing optoelectronic device under various photon energies. The device generated a high current density (J<sub>ph</sub>) of up to 2.2 mA/cm² and a photoresponsivity (R) of up to 22.0 mA/W, demonstrating its high sensitivity and technical advantages. This vdW material can be quickly and cheaply produced in large quantities, making it a promising option for light-capturing applications. Graphene ; van der Waals force ; Oxide ; Heterojunction ; Band gap ; Superlattice ; Absorbance Graphene research and applications ; 2D Materials and Applications ; Boron and Carbon Nanomaterials Research
Authors: Qing-Yun Fang | Siyu Xia | Tingrui Li | Yuxi Gao | Xiaopeng Wu | Weipeng Li | Jie Han | Chengjian Zhu | Jin Xie
Source: Nature Communications (article, 2025-12-09)
Field: Chemistry — Organic Chemistry

Bidentate mixed-ligand strategy in dinuclear gold photoredox catalysis Dinuclear metal complexes have fascinated researchers for decades owing to their unique metal-metal interactions and electronic synergies, which often lead to unconventional reactivity and exceptional catalytic performance. Despite recent efforts in dinuclear gold photoredox catalysis, limited accessibility of structurally diverse architectures has hindered an in-depth understanding of the Au-Au cooperativity, ligand effect, and structure-property relationships. Here, we report a bidentate mixed-ligand strategy for the modular synthesis of unsymmetrical, tricoordinate dinuclear gold complexes featuring both bisphosphine (P^P) and bipyridine (N^N) ligands. Interestingly, photophysical and computational studies reveal that ligand-to-ligand charge transfer (LLCT), coupled with Au-Au interactions, drives excited-state charge redistribution, enabling inner-sphere single-electron transfer (ISET) for inert C-Br bond activation. These complexes can catalyze three-component carbonylative amidation of unactivated alkyl bromides with amines and CO (balloon) under mild conditions, affording amide products (64 examples) in up to 96% yield. Denticity ; Photoredox catalysis ; Alkyl ; Reactivity (psychology) ; Catalysis ; Ligand (biochemistry) ; Amide Radical Photochemical Reactions ; Asymmetric Hydrogenation and Catalysis ; Catalytic Cross-Coupling Reactions