jablonkagroup/rise_ai_scientists huggingface dataset:
Authors: Dohoon Cha | Sun‐Joon Min
Source: ChemistryOpen (article, 2025-11-27)
Field: Chemistry — Organic Chemistry

2,3‐Dichloro‐5,6‐Dicyano‐1,4‐Benzoquinone (DDQ)‐Mediated CC Bond Formation: Redox Strategies from Stoichiometric to Catalytic Systems 2,3-Dichloro-5,6-dicyano-1,4-benzoquinone (DDQ) has long been recognized as a versatile organic oxidant that mediates diverse transformations through single-electron transfer, hydride abstraction, and redox cycling. Beyond its classical stoichiometric role in oxidation and dehydrogenation, DDQ now serves as an efficient catalyst for carbon-carbon bond formation across thermal, photochemical, and electrochemical domains. In stoichiometric reactions, DDQ enables benzylic and allylic CH activation to generate oxocarbenium or iminium intermediates that couple with a broad range of nucleophiles, facilitating alkylation, arylation, cyanation, and annulation processes. In catalytic systems, DDQ participates in redox cycles where the DDQ/DDQH<sub>2</sub> couple is regenerated by oxidants such as O<sub>2</sub>, nitrites, or MnO<sub>2</sub>, offering mild and simple access to complex carbon frameworks. The scope further extends to asymmetric catalysis and radical-mediated cross-dehydrogenative coupling, providing sustainable routes to natural product-like scaffolds and biologically active molecules. This review highlights the progression of DDQ from a stoichiometric oxidant to a redox-active catalyst, emphasizing its growing utility in controlled, metal-free oxidative CC bond formation and its promise for next-generation sustainable synthesis. Stoichiometry ; Catalysis ; Redox ; Allylic rearrangement ; Iminium ; Electrochemistry Catalytic C–H Functionalization Methods ; Radical Photochemical Reactions ; Oxidative Organic Chemistry Reactions
Authors: Yoichi TAKASHIMA | Taku Sawayama | Nobuhiko Hosono | Takashi Uemura
Source: Angewandte Chemie International Edition (article, 2025-08-27)
Field: Chemistry — Inorganic Chemistry

Regioselective Separation and Extraction of Polyalkylthiophene by Metal–Organic Frameworks Here, we report a novel method for selectively extracting high-regioregularity (RR) poly(3-hexylthiophene) (P3HT) from crude mixtures using metal-organic frameworks (MOFs) as nanoporous separation media. This approach leverages a kinetically driven "threading" mechanism in one-dimensional MOF channels, which discriminate subtle differences in the bonding patterns, e.g., head-head and head-tail linkages, in the main chain. By employing both MOF column chromatography and batch-scale separation techniques, higher RR fractions of P3HT were readily extracted from a crude mixture containing lower RR fractions. Regioselectivity ; Extraction (chemistry) ; Separation (statistics) ; Environmental chemistry ; Chemistry ; Environmental science ; Chromatography ; Organic chemistry ; Computer science ; Catalysis Metal-Organic Frameworks: Synthesis and Applications ; Electrochemical Analysis and Applications ; Organic and Molecular Conductors Research
Authors: Liujing Wang | Lan Xu | Long Chen | Zhuang Wu | Zhaofan Li | Wenjie Xia
Source: Journal of Polymer Science (article, 2025-07-30)
Field: Materials Science — Polymers and Plastics

Elucidating the Role of Chain Stiffness in Conformational Behaviors of Conjugated Polymers in Dilute Solution via Coarse‐Grained Modeling ABSTRACT Conjugated polymers (CPs) are characteristically distinguished by their rigid π‐conjugated backbone and flexible side chains, which play a crucial role in determining their conformational behavior in solution—a key factor influencing their performance in organic optoelectronic devices. Using coarse‐grained molecular dynamics (CGMD) simulations, here, we systematically explore chain conformational behaviors of CPs in dilute solutions by elucidating the role of the backbone bending stiffness. By comparing flexible, semi‐flexible, and rigid chain backbones, our results show that the effect of chain stiffness becomes more pronounced in good solvents at lower temperatures as compared to poor solvents at relatively higher temperatures. Investigating temperature effects reveals that backbone stiffness barely influences the theta‐point parameter of solvent quality, indicating consistent equilibrium between attractive and repulsive forces despite varying rigidity values. Among the various molecular and processing parameters analyzed, the solvent quality parameter stands as the most significant one, driving CPs toward extended shapes in good solvents vs. causing compact collapse in poor solvents. Furthermore, our scaling analysis determines the mass scaling exponent as a reliable structural indicator across diverse CP chain stiffnesses and topologies, offering a dimensionless metric that connects simulation results with experimental measurements. These findings contribute to a deeper understanding of polymer solution behavior and offer valuable design principles for optimizing CP‐based materials for their functional applications. Conjugated system ; Polymer ; Chain (unit) ; Stiffness ; Materials science ; Polymer chemistry ; Chemistry ; Polymer science ; Composite material ; Physics Conducting polymers and applications ; Polymer Nanocomposites and Properties ; Polymer crystallization and properties
Authors: Zongsu Han | Tiankai Sun | Peng Cheng | Wei Shi
Source: Communications Chemistry (article, 2025-07-17)
Field: Materials Science — Materials Chemistry

Cation-induced enhanced enantioselective recognition by a chiral covalent-organic framework Chirality plays a pivotal role in the properties of biologically active molecules, with enantiomers exhibiting divergent pharmacological and toxicological profiles. Enantioselective recognition is thus crucial in drug development, asymmetric synthesis, and environmental monitoring. Luminescence sensing has emerged as a powerful strategy for enantioselective recognition due to its fast response and visual readout capabilities. Covalent-organic frameworks (COFs) offer a promising platform for such applications by combining structural robustness, modular functionality, and inherent porosity. However, achieving both high enantioselectivity and quantitative sensing within a single system remains highly challenging. Herein, we present a cation-induced strategy for enantioselective sensing using a terbium-loaded chiral COF, Tb@CD-COF. Through a facile cation exchange of piperazine cations of CD-COF with Tb<sup>3+</sup> ions, we revealed a synergistic integration of cation-enhanced luminescence and chiral cavity-based enantioselective recognition mechanism. Tb@CD-COF demonstrates visually discernible colorimetric responses and quantitative enantiomer discrimination, offering a robust and efficient platform for advanced enantioselective sensing applications. Enantioselective synthesis ; Chirality (physics) ; Enantiomer ; Combinatorial chemistry ; Luminescence ; Covalent bond ; Chemistry ; Rational design ; Nanotechnology ; Materials science ; Stereochemistry ; Organic chemistry ; Catalysis Covalent Organic Framework Applications ; Luminescence and Fluorescent Materials ; Metal-Organic Frameworks: Synthesis and Applications
Authors: Belén García-Jarana | Diego Valor | Ignacio García-Casas | Jezabel Sánchez‐Oneto | Casimiro Mantell | Juan R. Portela | C. Pereyra
Source: Polymers (article, 2025-11-20)
Field: Materials Science — Polymers and Plastics

Hydrothermal Treatment to Enhance Supercritical CO2 Polycaprolactone Foaming Processes for Tissue Engineering Scaffolds Hydrothermal treatment was investigated as a strategy to enhance the supercritical CO<sub>2</sub> foaming process for the fabrication of polycaprolactone (PCL) scaffolds intended for tissue engineering applications. PCL samples were subjected to supercritical foaming at 300 bar and 40 °C for 60 min, combined with hydrothermal treatments performed either before or after foaming at temperatures of 70-100 °C and pressures of 10-20 bar. The effects of these treatments on scaffold morphology, porosity, and mechanical behavior were evaluated using scanning electron microscopy, micro-computed tomography, and compression testing. The results showed that hydrothermal treatment prior to foaming significantly improved scaffold porosity from 16.5% (untreated PCL) up to 57.9% while increasing pore interconnectivity (up to 156.8 throats mm<sup>-3</sup>). Conversely, post-foaming hydrothermal treatment led to pore collapse and loss of structural integrity. The pre-treated scaffolds maintained compressive moduli within 2-12 MPa, consistent with values required for bone tissue engineering. In vitro degradation in PBS revealed a moderate increase in weight loss (~10% after 90 days), indicating that the hydrothermal step slightly accelerates polymer hydrolysis without compromising stability. These findings demonstrate that combining hydrothermal pre-treatment with supercritical CO<sub>2</sub> foaming provides a solvent-free route to tailor scaffold morphology and mechanical performance, offering a sustainable alternative for the design of bioresorbable materials in regenerative medicine. Supercritical fluid ; Hydrothermal circulation ; Polycaprolactone ; Scaffold ; Porosity ; Tissue engineering ; Supercritical carbon dioxide Polymer Foaming and Composites ; Cellular and Composite Structures ; Botulinum Toxin and Related Neurological Disorders
Authors: Nicolas Cosanne | Daniel Cruz | Pierfrancesco Ticali | Hamidreza Hajiyani | Shilong Chen | Patrick Zeller | Thomas Götsch | Alexander Klyushin | Axel Knop‐Gericke | Martin Muhler | Beatriz Roldán Cuenya | R. Schlögl | Malte Behrens | Sharif Najafishirtari
Source: ChemRxiv (preprint, 2025-09-09)
Field: Materials Science — Materials Chemistry

Dynamic Surface Restructuring and Carbonate-Mediated Pathways in Perovskite-Catalyzed CO Oxidation Revealed by Operando Spectroscopy In this work, we studied two perovskite-based catalysts, namely LaFeO₃ (LFO) and LaFe₀.₇₅Co₀.₂₅O₃ (LFCO), to reveal the reaction mechanism and disentangle the complex surface phenomena taking place during a seemingly simple CO oxidation reaction. Precise kinetic measurements and operando spectroscopy were employed to elucidate the interplay between the formation of surface intermediates and the transformations of the surface sites, leading to the occurrence of a frustrated phase transition that can potentially define the catalyst activity under different reaction conditions. Our work specifically highlighted the effect of partial cobalt substitution into the perovskite’s structure on improving the activity of the reference iron-containing lanthanum-based perovskite. In this regard, modulation-excitation spectroscopy coupled with phase-sensitive detection (MES-PSD) and near-ambient pressure X-ray photoelectron spectroscopy (NAP-XPS) were employed at different temperatures to elucidate the multifaceted role of cobalt in promoting the carbonate-mediated pathway for CO oxidation. For LFO, kinetic and theoretical analyses confirm a pure Mars-van Krevelen (MvK) mechanism mediated by bidentate carbonates, yielding low activity but high stability. In contrast, LFCO exhibits higher activity (despite slight deactivation) through a dual MvK/Langmuir-Hinshelwood (LH) pathway. Monodentate carbonates act as low-temperature and unstable intermediates, with LFCO accelerating carbonate-to-CO₂ conversion via enhanced surface oxygen mobility. The temperature also dictates mechanistic shifts: LH dominates below 170°C, while MvK prevails above this threshold. Additionally, operando NAP-XPS reveals this transition coincides with cobalt reduction, iron oxidation, and frustrated phase transitions that activate carbonate intermediates. In our catalytic systems, cobalt serves as the primary active site, while lanthanum stabilizes the perovskite structure and surface carbonates, and iron maintains charge balance. These findings demonstrate how composition and temperature govern dynamic surface restructuring and reaction pathways in perovskite catalysts. Cobalt ; Catalysis ; X-ray photoelectron spectroscopy ; Perovskite (structure) ; Spectroscopy ; Transition metal ; Reaction mechanism Catalytic Processes in Materials Science ; Catalysis and Oxidation Reactions ; Catalysts for Methane Reforming
Authors: Daniele G. Mesquita | Mário Lúcio Moreira | José Luis Villca Villegas | Maria E. Gomes | Jorge Pimentel | E. Longo | Pedro Silva
Source:  (preprint, 2025-07-21)
Field: Materials Science — Electronic, Optical and Magnetic Materials

Defect-Induced Magnetism in Cerium-Doped Barium Zirconate Perovskites: A Systematic EPR Study of Oxygen Vacancies and Dopant Effects This study presents a systematic investigation of the magnetic and structural properties of cerium-doped barium zirconate (BaZr₁₋ₓCeₓO₃, x = 0.005-0.04) perovskites synthesized via a microwave-assisted hydrothermal method. X-ray diffraction (XRD) conf Dopant ; Doping ; Materials science ; Electron paramagnetic resonance ; Cerium ; Magnetism ; Oxygen ; Barium ; Condensed matter physics ; Inorganic chemistry ; Nuclear magnetic resonance ; Chemistry ; Metallurgy ; Optoelectronics ; Physics Magnetic and transport properties of perovskites and related materials ; Advanced Condensed Matter Physics ; Perovskite Materials and Applications
Authors: Jin Hu | Xuefeng Wang
Source: ChemPhysChem (article, 2025-04-15)
Field: Chemistry — Organic Chemistry

Metalized Borylene: A New Inorganic Cousin of Borylenes Borylenes have become a heated topic of intense interest due to their fascinating transition metal-mimicking reactivity and their role as key intermediates in synthesizing complex boron-containing molecules. However, the practical utilization of borylenes has been limited by their instability and complicated methodologies. Very recently, metalized borylenes based on boron-metal covalent interactions and stabilization strategies involving boron-metal multicenter bonding have been proposed. Spectroscopic and theoretical evidence has substantiated that metal-stabilized metalized borylenes possess molecular activation abilities comparable to or even superior to those of classical organoborylenes; however, these species are yet to be isolated or realized experimentally. This brief concept presents an overview of the definition, structural and bonding characteristics, stabilization strategies, amphoteric reactivity, experimental cases, and future perspectives of metal-stabilized metalized borylene compounds. As a new member of the borylene family, metal-stabilized metalized borylenes unlock new access to hyperactive amphoteric borylene, paving the way for synthesizing novel chemicals and developing new catalytic reactions. Reactivity (psychology) ; Boron ; Covalent bond ; Chemistry ; Metal ; Transition metal ; Nanotechnology ; Molecule ; Combinatorial chemistry ; Computational chemistry ; Materials science ; Catalysis ; Organic chemistry Organoboron and organosilicon chemistry ; Catalytic Cross-Coupling Reactions ; Synthesis and characterization of novel inorganic/organometallic compounds
Authors: Lanlan Deng | Xiaodong Xu | Zhan’ao Tan
Source: Nano Research (article, 2025-07-10)
Field: Chemistry — Spectroscopy

Recent progress of reversible thermochromic hydrogels and their application in smart windows Thermochromic hydrogel smart windows represent a significant breakthrough in the field of building energy conservation, offering a revolutionary solution for intelligent thermal environment management through their ability to dynamically regulate solar transmittance. This review systematically summarizes the thermoresponsive properties and technical bottlenecks of thermochromic hydrogels in smart window applications. A comprehensive analysis of the advantages and limitations of this class of material in terms of phase transition temperature, optical performance, stability, and response speed is provided, while the progresses made in optimizing their performance through various strategies are discussed. As a prospect, in the future, the development of thermochromic hydrogel smart windows must prioritize broad-temperature adaptability, cost-effectiveness, and multifunctional integration to address current challenges and facilitate their widespread adoption and scientific innovation in building energy conservation. Thermochromism ; Self-healing hydrogels ; Nanotechnology ; Materials science ; Smart material ; Chemistry ; Polymer chemistry ; Organic chemistry Aerogels and thermal insulation
Authors: Hitoshi Kumagai | Satoshi Kawata | Nobuhiro Ogihara
Source: Acta Crystallographica Section E Crystallographic Communications (article, 2025-04-24)
Field: Chemistry — Inorganic Chemistry

Crystal structure of poly[[aqua(μ<sub>2</sub>-pyrazine-κ<sup>2</sup> <i>N</i>:<i>N</i>′)(μ<sub>2</sub>-2,3,5,6-tetrachlorobenzene-1,4-dicarboxylato-κ<sup>2</sup> <i>O</i> <sup>1</sup>:<i>O</i> <sup>4</sup>)copper(II)] hemihydrate] The asymmetric unit of the title compound, {[Cu<sub>2</sub>(C<sub>8</sub>Cl<sub>4</sub>O<sub>4</sub>)<sub>2</sub>(C<sub>4</sub>H<sub>4</sub>N<sub>2</sub>)<sub>2</sub>(H<sub>2</sub>O)<sub>2</sub>]·H<sub>2</sub>O} <sub><i>n</i></sub> or {[Cu<sub>2</sub>(Cl<sub>4</sub>bdc)<sub>2</sub>(pyz)<sub>2</sub>(H<sub>2</sub>O)<sub>2</sub>]·H<sub>2</sub>O} <sub><i>n</i></sub> comprises of a Cu<sup>II</sup> ion, one tetra-chloro-benzene-dicarboxyl-ate ion (Cl<sub>4</sub>bdc<sup>2-</sup>), one pyrazine ligand (pyz), and one and a half water mol-ecules. The Cu<sup>II</sup> ion exhibits a five-coordinated square-pyramidal geometry with a CuN<sub>2</sub>O<sub>3</sub> coordination environment comprising two oxygen atoms of the Cl<sub>4</sub>bdc<sup>2-</sup> ligands, one oxygen atom of a water mol-ecule, and two nitro-gen atoms of the pyz ligands. The carboxyl-ate group is almost perpendicular to the benzene ring and shows monodentate coordination to the Cu<sup>II</sup> ion. The Cu<sup>II</sup> ions of these units are bridged by both the Cl<sub>4</sub>bdc<sup>2-</sup> and pyz ligands to form two-dimensional (2D) layers, which are linked by alternating hydrogen-bonding and C-Cl⋯π inter-actions to yield a three-dimensional network. Chemistry ; Crystallography ; Pyrazine ; Crystal structure ; Ligand (biochemistry) ; Carboxylate ; Denticity ; Molecule ; Ion ; Ring (chemistry) ; Hydrogen bond ; Stereochemistry Metal-Organic Frameworks: Synthesis and Applications ; Crystal structures of chemical compounds ; Magnetism in coordination complexes
Authors: Yun Lee | Sung Kyu Maeng | Ki Bong Lee | Jae‐Woo Choi | Youngkyun Jung
Source: Advanced Composites and Hybrid Materials (article, 2025-10-01)
Field: Chemistry — Organic Chemistry

Controlled in-situ crystallization in amine-rich millicapsules for hyper-efficient copper recovery Abstract Sustainable copper (Cu) circulation is critical for both environmental protection and industrial advancement, as Cu is an essential material in electronics, energy storage, and catalysis. However, conventional adsorbents struggle with low efficiency and poor selectivity when recovering Cu from large wastewater volumes, leading to resource loss and secondary pollution. This study introduces diethylenetriamine (Dien)-rich millicapsules (DMCs) with ion-transferring porous frameworks designed for capacitive, stable, and highly selective Cu recovery from complex liquid environments. The unique three-dimensional center-radial frameworks significantly enhance Cu 2+ ion transport to the capsule core, ensuring efficient capture and crystallization. Simultaneously, hierarchical pores with high surface curvature increase Dien density, promoting rapid Cu nucleation and controlled crystal growth. Large internal voids provide ample space for dense Cu 2 (OH) 3 NO 3 crystal formation, achieving Cu 2+ adsorption capacity of 1602.30 mg g –1 and ensuring long-term recovery stability. Additionally, a nanoporous shell prevents crystal leakage while blocking suspended solids, maintaining structural integrity. Through a synergistic chelation–crystallization mechanism, the DMCs achieve unprecedented Cu 2+ adsorption capacity and selectivity, with effective regeneration for seven repetitive adsorption–desorption cycles. This novel transition from conventional 2D surfaces to advanced 3D spaces not only enhances resource recovery but also contributes to sustainable metal recycling, resource security, and the circular economy. Graphical abstract Adsorption ; Copper ; Crystallization ; Nanoporous ; Porosity ; Nucleation ; Resource recovery ; Bimetal Nanomaterials for catalytic reactions ; Extraction and Separation Processes ; Supercapacitor Materials and Fabrication
Authors: Samuel M. Shabangu | Alan C. Eaby | Sousa Javan Nikkhah | Lilia Croitor | Tao He | Andrey A. Bezrukov | Matthias Vandichel | Michael J. Zaworotko
Source: Journal of Materials Chemistry A (article, 2025-01-01)
Field: Chemistry — Inorganic Chemistry

A pcu topology metal–organic framework, Ni(1,4-bib)(inca) <sub>2</sub> , that exhibits high CO <sub>2</sub> /N <sub>2</sub> selectivity and low water vapour affinity Herein we report the synthesis of a new metal-organic framework, Ni(1,4-bib)(inca)<sub>2</sub> or pcu-1-Ni, where 1,4-bib = 1,4-bis(imidazole-1-yl)benzene, inca = indazole-5-carboxylic acid, through the crystal engineering strategy of using an N-donor linker to pillar a square lattice, sql, topology net. pcu-1-Ni adopts pcu topology and features two types of hydrophobic pore, small pore A and large pore B. The biporous nature of pcu-1-Ni is reflected in its stepped CO<sub>2</sub> and H<sub>2</sub>O adsorption isotherms, highlighting the influence of pore size and chemistry on gas and water vapour sorption properties. pcu-1-Ni exhibits the unusual combination of high CO<sub>2</sub>/N<sub>2</sub> selectivity (IAST selectivity 100-250) and low water affinity at low RH (an S-shaped water vapour isotherm with an inflection point at 45-65% RH). Whereas pcu-1-Ni degrades upon repeated exposures to water vapour, its structure-property relationships can provide guidance for design of the next generation of CO<sub>2</sub>-selective sorbents. In this context, Canonical Monte Carlo simulations provide insight into the preferential adsorption of CO<sub>2</sub> over N<sub>2</sub> and H<sub>2</sub>O. Selectivity ; Metal ; Metal-organic framework ; Topology (electrical circuits) ; Materials science ; Chemistry ; Chemical engineering ; Organic chemistry ; Adsorption ; Mathematics Metal-Organic Frameworks: Synthesis and Applications ; Magnetism in coordination complexes ; Crystallography and molecular interactions