jablonkagroup/rise_ai_scientists huggingface dataset:
Authors: Ivan Tambovtsev | Óskar Kristinsson | Hannes Jónsson
Source: ArXiv.org (preprint, 2025-10-09)
Field: Chemistry — Organic Chemistry

The Effect of Chlorine Substitution on Rotational Speed and Light Absorption of Second Generation Molecular Motors The effect of substituting a hydrogen atom by a chlorine atom or a methyl group by a trichloromethyl (CCl3) group at the stereogenic center of light-driven second generation molecular motors is calculated in order to assess the effect on rotational speed and the separation of the absorption peaks of the isomers. While experimental and theoretical studies have previously been carried out for fluorine substitution, this is the first study of chlorine substitution. Five well-characterized base molecules are studied and the trends are compared with the effect of fluorine substitution. The trichloromethyl substitution is found to accelerate the rotation more than a trifluoromethyl (CF3) substitution by reducing the life-time of the metastable state, due to larger steric hindrance in the metastable state than in the transition state for the thermal helix inversion (THI). A larger increase in the separation of the absorption peaks of the two isomers is also obtained. The Cl atom substitution, however, changes the energy landscape significantly, making the M isomer lower in energy than the P isomer, and raising the energy barrier for THI beyond that of the back transition, thus quenching the rotation. Fluorine ; Metastability ; Steric effects ; Molecule ; Trifluoromethyl ; Hydrogen atom ; Excited state ; Quenching (fluorescence) Supramolecular Chemistry and Complexes ; Geophysics and Sensor Technology ; Mechanical and Optical Resonators
Authors: Cristina Leonelli | Elena Colombini | Cecilia Mortalò
Source: Preprints.org (preprint, 2025-11-19)
Field: Chemistry — Organic Chemistry

&lt;p class="MsoNormal" style="margin-bottom: 12.0pt; text-align: left; mso-line-height-alt: 14.0pt; layout-grid-mode: char; mso-layout-grid-align: none; border: none; mso-padding-alt: 31.0pt 31.0pt 31.0pt 31.0pt; mso-border-shadow: yes;" align="left"&gt;Contribution of Microwave Irradiation in the Synthesis of Inorganic Compounds: An Italian Approach Microwave heating has a good number of advantages in the synthesis of inorganic compounds when opportunely exploited. A deep knowledge of the interaction of the electromagnetic waves and matter is necessary to optimize irradiation of the reactor vessel so that to obtain homogeneous heating for homogeneous nucleation and growth of particle, localized heating of starting self-sustained high temperature synthesis and generate superfast heating and cooling profile to get metastable crystals. Case studies of pure oxides, mixed oxides, composites, phosphates, zeolites, and high entropy alloys have been discussed in the international frame of the academic and industrial research covering the last 20 years of microwave chemistry where Italian researchers covered a relevant role. Microwave ; Homogeneous ; Microwave irradiation ; Nucleation ; Irradiation ; Metastability Microwave-Assisted Synthesis and Applications ; Ammonia Synthesis and Nitrogen Reduction ; Zeolite Catalysis and Synthesis
Authors: Nicole Maximo dos Santos | Martha Freire Silva | Alexandre Ferreira Young | Marcos L. Dias | Mariana M.V.M. Souza
Source: Reactions (article, 2025-09-24)
Field: Chemistry — Organic Chemistry

Ethylene and 1-butene Oligomerization with Benzimidazole Complexes of Nickel and Iron: A Case of Tandem Reaction The coordination chemistry of benzimidazole ligands combines σ donation and π backbonding. Owing to this electronic flexibility, benzimidazole ligands stabilize both electron deficient and electron-rich transition states in the catalytic cycle of Ziegler-Natta polymerizations. In this study, Fe(III) and Ni(II) complexes of 2-substituted-benzimidazoles were tested as catalysts for ethylene and 1-butene oligomerization. The tests realized in toluene yielded mainly butenes and minor amounts of hexenes. When dichloromethane was used as solvent, a tandem reaction took place and 1-butene produced by ethylene dimerization was further oligomerized, yielding octenes and dodecenes as main products. All tested catalysts exhibited moderate selectivity for 1-octene, indicating 1-ω enchainment in 1-butene dimerization. Beyond catalytic tests, a theoretical study of the ligand 2,2′-(furan-2,5-diyl)bis(1H-benzimidazole) confirmed the planar structure of this compound as evidenced by NMR spectroscopy. Benzimidazole ; Catalysis ; Ethylene ; Nickel ; Selectivity ; Ligand (biochemistry) ; Dichloromethane ; Toluene Organometallic Complex Synthesis and Catalysis ; Asymmetric Hydrogenation and Catalysis ; Catalysis and Oxidation Reactions
Authors: Rajni Rajni | Chinmay Mittal | Prabhjot Kaur | Neera Raghav | Sneh Lata | Anjaneyulu Bendi
Source: ChemistrySelect (article, 2025-07-01)
Field: Chemistry — Organic Chemistry

Green Catalysis for Dihydropyrimidinone Synthesis Using Copper‐Doped Carbon Quantum Dots: Computational and Experimental Pepsin Inhibition Studies Abstract The current work provides a novel green method for creating dihydropyrimidinone (DHPM) scaffolds utilizing copper‐doped carbon quantum dots (Cu‐CQDs) as an environment‐friendly and effective heterogeneous catalyst in the search for a green and sustainable catalytic approach. In accordance with green chemistry principles, Cu‐CQDs catalytic effectiveness was proven in the Biginelli reaction, producing DHPM derivatives in mild, solvent‐free conditions. Additionally, using in silico DFT and molecular docking studies, the produced DHPM compounds were assessed first time for their ability to block the pepsin enzyme, demonstrating robust binding interactions inside the active site of the enzyme. Based on the promising docking results, all the DHPM derivatives were subjected to in vitro enzymatic assay, confirming their potential as effective pepsin inhibitors with inhibition ranging from 1.99 ± 0.9 M to 8.98 ± 1.9 M at a concentration of 10 −6 M. The obtained IC 50 value of 1.99 ± 0.9 × 10 −6 M indicated that the compound RJ10 was the best inhibitor. Cu‐CQDs catalyzed DHPMs emerged as a novel class of pepsin inhibitors with potential applications in medicinal chemistry is highlighted by the combined computational and experimental insights. This study provides the pathway for further developments of DHPM derivatives as digestive enzyme inhibitors. Copper ; Catalysis ; Pepsin ; Quantum dot ; Doping ; Carbon quantum dots ; Carbon fibers ; Chemistry ; Materials science ; Chemical engineering ; Nanotechnology ; Inorganic chemistry ; Metallurgy ; Composite material ; Organic chemistry ; Composite number ; Enzyme ; Optoelectronics Multicomponent Synthesis of Heterocycles ; Synthesis and Biological Evaluation ; Microwave-Assisted Synthesis and Applications
Authors: Yongping Chen | Xingde Li
Source: bioRxiv (Cold Spring Harbor Laboratory) (preprint, 2025-04-05)
Field: Materials Science — Polymers and Plastics

pH-Sensitive Optical Nanocomposites Using Polymer-Coated Gold Nanorods pH-Sensitive Polymer-Coated Gold Nanorods for Reversible SPR Shifts and Applications in pH Sensing as Optical Materials. Nanorod ; Nanocomposite ; Materials science ; Polymer ; Nanotechnology ; Polymer nanocomposite ; Optoelectronics ; Composite material Conducting polymers and applications ; Advanced Nanomaterials in Catalysis ; Gold and Silver Nanoparticles Synthesis and Applications
Authors: Xufeng Yang | Debiao Liu | Long Chen | Zhixue Zhang
Source: Zeitschrift für Kristallographie - New Crystal Structures (article, 2025-04-28)
Field: Chemistry — Inorganic Chemistry

Crystal structure of poly[( <i>μ</i> <sub>2</sub> -1,4-bis(imidazol-1-yl)benzene- <i>k</i> <sup>2</sup> <i>N:N</i> ′)( <i>μ</i> <sub>4</sub> -biphenyl-3,3′,5,5′-tetracarboxylic- <i>k</i> <sup>4</sup> <i>O</i> , <i>O</i> , <i>O</i> , <i>O</i> )dizinc(II)] dihydrate, C <sub>40</sub> H <sub>28</sub> Zn <sub>2</sub> N <sub>8</sub> O <sub>9</sub> Abstract C 40 H 28 Zn 2 N 8 O 9 , orthorhombic, Fdd 2 (no. 43), a = 26.725(3) Å, b = 26.450(2) Å, c = 10.1498(8) Å, V = 7174.7(11) Å 3 , Z = 8, R gt ( F ) = 0.0486, wR ref ( F 2 ) = 0.0981, T = 293(2) K. Benzene ; Biphenyl ; Crystal structure ; Crystal (programming language) ; Crystallography ; Chemistry ; Physics ; Medicinal chemistry ; Organic chemistry ; Computer science Metal-Organic Frameworks: Synthesis and Applications ; Magnetism in coordination complexes ; Polyoxometalates: Synthesis and Applications
Authors: Ido Domb | Nathan W. Levin | Anas Abo Raed | Hadas Shalit Peleg | Danilo M. Lustosa | Yury V. Torubaev | Anat Milo
Source: ChemRxiv (preprint, 2025-09-17)
Field: Chemistry — Inorganic Chemistry

Enhanced Reactivity and Selectivity in Organocatalysis via In-Situ Proline-Boronic Acid Complex Modification The aldol reaction is a pivotal carbon-carbon bond-forming process integral to the biosynthesis of natural compounds. Yet, its application remains limited due to the challenges of selectivity, stereochemistry, and reaction efficiency. Herein, we report a boronic acid (BA)-modified proline catalyst system that significantly enhances both reactivity and selectivity in asymmetric aldol reactions, particularly for unbranched linear aliphatic aldehydes, a long-standing challenge in synthetic chemistry. Employing dynamic covalent and non-covalent interactions, BA acts as a secondary-sphere modifier, forming a catalytic pocket that emulates enzymatic processes. This system enables high diastereo- and enantioselectivity under mild conditions across a broad substrate scope, including challenging aldehydes and ketones, and demonstrates gram-scale applicability in synthesizing (+)-Disparlure, a bioactive natural product. Mechanistic investigations, including NMR and crystallographic studies, reveal the critical role of BA in modulating the catalyst microenvironment, achieving unprecedented selectivity and efficiency. Aldol reaction ; Selectivity ; Reactivity (psychology) ; Catalysis ; Organocatalysis ; Substrate (aquarium) ; Boronic acid ; Covalent bond Asymmetric Hydrogenation and Catalysis ; Organometallic Complex Synthesis and Catalysis ; Catalytic Cross-Coupling Reactions
Authors: Mathias van der Veer | Nick Daems | Pegie Cool | Tom Breugelmans
Source: EES Catalysis (article, 2025-10-15)
Field: Materials Science — Materials Chemistry

Thin-film Cu <sub> 1− <i>x</i> </sub> N <sub> <i>x</i> </sub> catalysts for efficient CO <sub>2</sub> reduction: a scalable magnetron sputtering approach Reactive sputtering of N 2 , through physical vapor deposition, fabricated N-containing Cu thin films that serve as an efficient alternative compared to metallic Cu for the electrochemical CO 2 reduction. Sputtering ; Sputter deposition ; Catalysis ; Thin film ; Physical vapor deposition ; Metal Catalytic Processes in Materials Science ; CO2 Reduction Techniques and Catalysts ; Copper-based nanomaterials and applications
Authors: Federica Palmeri | Venanzio Raglione | Laura Mancini | Gloria Zanotti
Source: Organic Chemistry Frontiers (article, 2025-12-23)
Field: Materials Science — Materials Chemistry

A versatile and practical one-pot strategy for a greener, waste-minimized synthesis of aryloxy- and alkyloxy-substituted metallophthalocyanines <i>via</i> tandem S <sub>N</sub> Ar-cyclotetramerization A sustainable one-pot S N Ar-cyclotetramerization reaction affords metallophthalocyanines with broad functional group tolerance, higher efficiency, and ≥90% lower E -factors than the literature values. Tandem ; Functional group ; Reaction conditions ; Cascade reaction Porphyrin and Phthalocyanine Chemistry ; Vanadium and Halogenation Chemistry ; Synthesis and Characterization of Pyrroles
Authors: Maria Ulfa | Indriyani Pangestuti
Source: Communications in Science and Technology (article, 2025-07-31)
Field: Materials Science — Materials Chemistry

Effect of ratio Pluronic P123 and gelatin on titania as a catalyst in methylene blue degradation This study explores the influence of the gelatin-to-Pluronic P123 molar ratio on the synthesis, structural properties, and photocatalytic performance of titania for methylene blue degradation. Gelatin, employed as a biotemplate alongside Pluronic P123, effectively modulates the physicochemical characteristics of titania. As the gelatin content increases, significant changes are observed in oxygen incorporation, pore morphology, and crystallinity. Energy-dispersive X-ray spectroscopy (EDX) reveals a progressive increase in surface oxygen content from 10% (T-Gl) to 29% (T-Gh), indicating strong interactions between gelatin’s NH? groups and titanium species. FTIR analysis confirms enhanced Ti–O–Ti bonding, with peak transmittance intensities reaching 79.857% in T-Gh. Nitrogen adsorption-desorption measurements verify mesoporosity across all samples, with pore diameters ranging from 12.4 nm to 14.8 nm and surface areas from 27.69 to 31.67 m²/g. Crystallite sizes, determined by XRD, range between 4.27 nm and 8.56 nm, while the crystallinity varies from 45.81% to 54.55%. Despite having a lower surface area, T-Gm exhibits excellent photocatalytic efficiency (90.23%) due to favorable pore and crystallite characteristics. T-Gh demonstrates the highest performance (92.90%), attributed to its oxygen-rich surface, moderate crystallinity, and balanced mesoporous framework that enhances charge separation and dye adsorption. These findings underscore the critical role of gelatin-to-P123 ratio control in tailoring structural and surface functionalities of titania, thereby offering a sustainable strategy for designing efficient photocatalysts for environmental remediation. The developed biotemplated synthesis approach not only enhances photocatalytic performance but also promotes the use of eco-friendly and cost-effective materials, making it highly beneficial for scalable applications in wastewater treatment. Methylene blue ; Gelatin ; Poloxamer ; Degradation (telecommunications) ; Catalysis ; Chemical engineering ; Materials science ; Methylene ; Nuclear chemistry ; Chemistry ; Copolymer ; Organic chemistry ; Composite material ; Polymer ; Computer science ; Photocatalysis Advanced Nanomaterials in Catalysis ; Advanced Photocatalysis Techniques ; Microplastics and Plastic Pollution
Authors: Ya Li | Da Song | Shengxi Zhao | Fang He | Hongyu Huang | Li Feng | Zheng Liu | Cuiqin Li | Zhen Huang
Source: Small (article, 2025-12-24)
Field: Chemistry — Inorganic Chemistry

Dual‐Site Single‐Atom Ni Catalysts for Highly Efficient Ethylene Oligomerization to 1‐Hexene The shale revolution has reshaped the global energy landscape, making ethane an efficient feedstock for ethylene production, which has created a market scarcity of higher α-olefins, such as butene and hexene. Therefore, the ethylene oligomerization of abundant ethylene to produce higher α-olefins offers significant advantages. However, substantial challenges remain in enhancing the product separation and catalyst recyclability during ethylene oligomerization. We propose a directed coordination strategy based on covalent organic framework (COF) structures, wherein metal active centers are precisely anchored to yield atomic-level degrees of dispersion within the frameworks. This approach effectively avoids catalyst deactivation induced by aggregation while exposing a higher number of active sites. The highly dispersed single-atom catalyst NPP@Ni exhibits an exceptional activity (10.96 × 10<sup>5</sup> g/(mol Ni⋅h)<sup>-1</sup>) and a high selectivity toward hexene (>66.5%) across multiple catalytic cycles. The rational design of COF topologies enables the systematic regulation of the coordination environments and electronic structures of Ni sites. The catalytic performance and theoretical density functional theory calculations suggest that the coordination environment of Ni correlates directly with the selectivity toward α-olefins. This study provides novel insights into the design of highly efficient and stable ethylene oligomerization catalysts. Ethylene ; Catalysis ; Selectivity ; Yield (engineering) ; Dispersion (optics) ; Covalent bond ; Rational design ; Density functional theory Metal-Organic Frameworks: Synthesis and Applications ; Covalent Organic Framework Applications ; Zeolite Catalysis and Synthesis
Authors: E. Vildan Burgaz | Mahya Tanha | Seyed Armin Houshmand Kia
Source: Journal of the Turkish Chemical Society Section A Chemistry (article, 2025-11-03)
Field: Chemistry — Organic Chemistry

Rational Design, Synthesis, and Comprehensive Characterization of Novel 1,4-Pentadien-3-one Derivatives Bearing Oxime Moieties The purpose of this research is to synthesize a series of novel 1,4-pentadien-3-one oximes and 1,4-pentadien-3-one O-benzoyl oximes. In this work, new 1,4-pentadien-3-one derivatives with oxime moieties are logically designed, synthesized, and thoroughly characterized. Using a multi-step synthetic strategy, a number of 1,4-pentadien-3-one derivatives were created by functionalizing the core structure with oxime functionalities. The structures of the newly synthesized compounds were determined by several spectroscopic methods, including Nuclear Magnetic Resonance Spectroscopy (1H NMR, 13C NMR) and Mass Spectroscopy. Oxime ; Characterization (materials science) ; Nuclear magnetic resonance spectroscopy ; Bearing (navigation) ; Mass spectrometry ; Spectroscopy Synthesis and biological activity ; Synthesis of heterocyclic compounds ; Synthesis and Characterization of Heterocyclic Compounds
Authors: Phanlapa Borklom | Narathon Khemasiri | Sukittaya Jessadaluk | Prapakorn Rattanawarinchai | Navaphun Kayunkid | Sakon Rahong | Adirek Rangkasikorn | Supamas Wirunchit | Annop Klamchuen | Jiti Nukeaw
Source: Current Applied Science and Technology (article, 2025-06-23)
Field: Materials Science — Materials Chemistry

Tailoring ZnO Nanostructures through Precursor Concentration and Hydrothermal Duration: A Pathway to Efficient Solar Water Splitting This work investigated the formation of ZnO nanostructures on ITO substrates prepared by self-seeding hydrothermal synthesis for photoelectrochemical (PEC) water splitting applications. The hydrothermal parameters, precursor concentration and hydrothermal time, were varied to explore their influences on ZnO crystallinity, morphology, and PEC performance. The combinations of X-ray diffraction and field emission scanning electron microscopy revealed highly oriented ZnO nanostructures with diverse morphologies, including small granules, nanorods, dense films, and hexagonal platelets. Topographic profiling of the morphological parameters revealed complex relationships between synthesis conditions and nanostructure characteristics, highlighting the importance of considering aggregation phenomena in substrate-based growth. This aggregation led to deviations from conventional crystal growth theory predictions, particularly for grain density and diameter evolution. PEC performance evaluation identified ZnO nanorods as the optimal morphology, exhibiting a photocurrent density of 0.182 mA/cm² at 0 V vs. Ag/AgCl. Further enhancement was achieved by decorating ZnO nanorods with CdS nanoparticles, resulting in a six-fold increase in photocurrent density (1.2 mA/cm²). This improvement is attributed to expanded light absorption and improved charge separation at the CdS/ZnO interface. Our findings demonstrate the potential of rationally designed ZnO-based nanostructures in the advancement of solar-driven water splitting technologies and provide valuable insights for optimizing PEC systems through precise control of hydrothermal synthesis parameters, consideration of substrate-induced aggregation, and strategies for photoelectrochemical (PEC) water splitting applications. Nanorod ; Photocurrent ; Materials science ; Hydrothermal circulation ; Water splitting ; Crystallinity ; Nanostructure ; Nanotechnology ; Chemical engineering ; Hydrothermal synthesis ; Photocatalysis ; Optoelectronics ; Chemistry ; Composite material ZnO doping and properties ; Advanced Photocatalysis Techniques ; Ga2O3 and related materials
Authors: Handou Zheng | Guangshui Tu | Cheng Du | Heng Gao | Lixia Pei | Haiyang Gao
Source: NPG Asia Materials (article, 2025-02-06)
Field: Materials Science — Materials Chemistry

Degradable hypercrosslinked porous polymer generated from aromatic polyketone Abstract Although hypercrosslinked porous polymers as highly efficient adsorbents can remove pollutants, hypercrosslinked polymers (HCPs) themselves are also a source of white plastic pollution. Development of degradable HCPs is highly desirable based on the full environmental protection concept. In this paper, we reported the direct synthesis of hypercrosslinked polyketones (HCPK-X, X = H, O t Bu) generated from degradable aromatic polyketones via external crosslinking technique. The hypercrosslinked structure of HCPK-X was fully characterized, and HCPK-O t Bu had a mesopores structure (1.27–68.5 nm) and large surface area ( S BET = 321 m 2 /g). HCPK-O t Bu exhibits a good adsorption capability for aniline removal from aqueous solution, and its enhanced adsorption capability is ascribed to the interactions between aniline and the carbonyl and tert -butoxy groups. The photodegradation of hypercrosslinked polyketones was evaluated and emphasized. The prepared hypercrosslinked polyketones can rapidly and efficiently decompose under UV light irradiation, which represents the first sample of degradable hypercrosslinked polymers. Materials science ; Polymer ; Porosity ; Porous medium ; Chemical engineering ; Nanotechnology ; Organic chemistry ; Polymer chemistry ; Composite material ; Chemistry Covalent Organic Framework Applications ; Metal-Organic Frameworks: Synthesis and Applications ; Membrane Separation and Gas Transport
Authors: Marcello Casertano | Brian Kelly | Malachi W. Gillick‐Healy | Paolo Grieco | Mauro F. A. Adamo
Source: Organics (article, 2025-04-02)
Field: Chemistry — Organic Chemistry

Synthesis of Indole-Based Derivatives Containing Ammonium Salts, Diamines and Aminoureas for Organocatalysis Indole heterocycles have an established reactivity, and these compounds are H-bond donors via a peculiar non-basic NH. However, the indole core has been scarcely employed in organocatalysis, with only a few examples relevant to electrophilic halogenation reported. To expand the range of potential transformations achievable via indole catalysis, we have designed a set of new organic species incorporating an indole core, alongside three privelaged chiral moieties found in many known organocatalysts, namely a quaternary ammonium salt, a diamine and an amino-urea. Herein, we report an optimised synthetic route for the preparation of these potential catalytic species in an enantiomerically pure form. The syntheses are conceived to be modular and therefore will allow each of the three single organic catalysts to be expanded into families without alteration of the synthetic layout, therefore leading to a fast optimisation of new asymmetric procedures. Organocatalysis ; Indole test ; Chemistry ; Ammonium ; Organic chemistry ; Catalysis ; Combinatorial chemistry ; Enantioselective synthesis Asymmetric Synthesis and Catalysis ; Chemical Synthesis and Reactions ; Oxidative Organic Chemistry Reactions
Authors: Jana Glatz | Volodymyr Malytskyi | Rodrigue Lescouëzec
Source: Coordination Chemistry Reviews (article, 2025-11-16)
Field: Chemistry — Organic Chemistry

Cyanide cubic cages: soluble molecular counterparts of prussian blue analogues International audience Prussian blue ; Cyanide ; Blue light ; Cyanation Supramolecular Chemistry and Complexes ; Molecular Sensors and Ion Detection ; Luminescence and Fluorescent Materials