Article
Chemistry, Multidisciplinary
Zhitao Feng, Dean J. Tantillo
Summary: Carbocation rearrangement reactions are significant for synthetic and biosynthetic chemistry. Nonstatistical dynamic effects were found to play a crucial role in migratory aptitude.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2021)
Article
Chemistry, Multidisciplinary
Nicolaj Inunnguaq Jessen, Joseph A. Izzo, Marek S. Modlinski, Giulio Bertuzzi, Karl Anker Jorgensen
Summary: The development of higher-order cycloadditions has been limited due to the need for highly conjugated and reactive pi-systems. Recent research shows that organocatalysis can be an efficient mediator to overcome these challenges. Computational studies have also found that the impact of benzofusions on higher-order cycloadditions can be explained by changes in energy barriers.
CHEMISTRY-A EUROPEAN JOURNAL
(2023)
Article
Chemistry, Organic
Bruce A. L. Sacchelli, Bianca C. Rocha, Leandro H. Andrade
Summary: An ultrafast methodology utilizing microwave irradiation was employed for the first time to construct novel highly functionalized 2-quinolinones from N-(o-ethynylaryl)-acrylamides (1,7-enynes). The method involved six key consecutive reactions, including a diastereoselective step, to achieve good overall yield of 2-quinolinone-fused gamma-lactones (up to 46%; 10 s).
Review
Chemistry, Multidisciplinary
Titas Deb, Julian Tu, Raphael M. Franzini
Summary: This article reviews the mechanisms and substituent effects of some of the principal metal-free bioorthogonal reactions, based on inverse-electron demand Diels-Alder reactions, 1,3-dipolar cycloadditions, and the Staudinger reaction. Modified versions that link these reactions to a dissociative step are further discussed, with the aim to aid the advancement of bioorthogonal chemistry.
Article
Chemistry, Physical
Tim Glaesel, Haijun Jiao, Marko Hapke
Summary: In this study, the Co-II-catalyzed [2+2+2] cycloaddition of functionalized diynes and phosphaalkynes was reported, resulting in an array of structurally interesting phosphinines. The combination of dppbenz and CoI2 was found to be the most suitable and active catalyst system under microwave reaction conditions. Chemoselective cyclizations of phosphaalkynes in the presence of nitriles were observed, and various carbonyl functionalities were tolerated as well.
Review
Chemistry, Multidisciplinary
Guo-Qiang Xu, Peng-Fei Xu
Summary: In recent years, impressive progress has been made in the development of organic photoredox catalytic cascade reactions without the need for expensive and toxic transition metals, leading to the synthesis of chemically and biomedically valuable building blocks. This review highlights the recent advancements in this blooming area by introducing new catalytic cascade reactions mediated by organic photoredox catalysts and discussing their mechanisms and applications as reported in recent literature.
CHEMICAL COMMUNICATIONS
(2021)
Review
Chemistry, Multidisciplinary
Asier Carral-Menoyo, Nuria Sotomayor, Esther Lete
Summary: The palladium-catalyzed selective C-H alkenylation reaction is an efficient, economical, and environmentally friendly method for constructing carbon-carbon bonds. It provides a powerful tool for synthesizing conjugated organic molecules and enabling late-stage functionalization. The understanding of its mechanism and development of efficient chiral catalysts have expanded its application.
TRENDS IN CHEMISTRY
(2022)
Article
Chemistry, Organic
Manajit Das, Achyut Ranjan Gogoi, Raghavan B. Sunoj
Summary: In this paper, the molecular understanding of the role of protic solvents in organic transformations is explored using density functional and ab initio computational studies. The inclusion of explicit solvent molecules in crucial transition states has been found to improve the energetic estimates of organocatalytic and transition-metal-catalyzed reactions. An overview of the importance of an explicit-implicit solvation model is provided with the help of interesting examples.
JOURNAL OF ORGANIC CHEMISTRY
(2022)
Article
Chemistry, Organic
Rui-Xue Ji, Ning Liu, Jiang-Shan Shen
Summary: In this study, enantioselective amine exchange reactions were demonstrated for the first time using enantiomeric chiral amines and a series of innovative axially chiral 1,1'-binaphthyl-2,2'-diamine (BNDA)-based imines. The dynamic behavior was influenced by the electron-donating or electron-withdrawing capability of the substituent at position 4 or 5 of the salicylaldehyde part of the chiral imines. Additionally, the presence of o-OH groups in SA-based imines and protic solvents used as reaction media were found to be crucial for the high rate dynamic behavior.
JOURNAL OF ORGANIC CHEMISTRY
(2021)
Article
Chemistry, Multidisciplinary
Run-Kai Fang, Zheng-Chun Yin, Jun-Shen Chen, Guan-Wu Wang
Summary: A convenient and efficient [3 + 2] cycloaddition reaction of alkenes and alkynes with the in situ generated nitrile oxides from aldoximes in the presence of NaCl, Oxone and Na2CO3 has been developed to afford a series of isoxazoles and isoxazolines at room temperature in yields up to 85% and 86%, respectively. The current methodology exhibits a wide substrate scope, (hetero)aromatic and aliphatic aldoximes, alkenes including acrylate esters, acrylonitrile, chalcone, styrene, N-methylmaleimide and [60]fullerene, phenylacetylene, and alkynes containing CH2OH, SiMe3, COCH3 or CO2CH3 group can be employed. The present protocol features good functional group tolerance, short reaction time, mild reaction conditions and high atom economy, providing an efficient and environmentally friendly access to isoxazoles and isoxazolines.
GREEN CHEMISTRY LETTERS AND REVIEWS
(2022)
Review
Chemistry, Multidisciplinary
Santosh Kumar Nanda, Rosy Mallik
Summary: Vicinal carboamination of alkynes is a reliable and efficient strategy for the synthesis of valuable and diverse amine derivatives. While transition-metal catalysis has been extensively studied, metal-free alternatives are also gaining attention. However, scattered reports have hindered further developments in this field. This review discusses different approaches and provides examples from the literature, giving insight into the mechanisms of these transformations.
Article
Chemistry, Multidisciplinary
Nicole Houszka, Hannes Mikula, Dennis Svatunek
Summary: 1,2,4,5-Tetrazines are widely used in bioorthogonal chemistry for their high reactivity in Diels-Alder reactions. The substituents in the 3- and 6-positions of the tetrazine scaffold significantly affect the rate of cycloadditions, but this is not explained by frontier molecular orbital interactions. Instead, the high reactivity of mono-substituted tetrazines is due to decreased Pauli repulsion, leading to a more asynchronous approach and reduced distortion energy. Additionally, ethylene is not a good model compound for other alkenes in Diels-Alder reactions.
CHEMISTRY-A EUROPEAN JOURNAL
(2023)
Review
Chemistry, Multidisciplinary
Ian A. Tonks
Summary: This study discusses the recent progress in Ti-catalyzed oxidative amination reactions, highlighting the importance of understanding the reactive species and mechanisms involved. The research shows that low-valent Ti intermediates can be stabilized through coordination and that reductive elimination processes occur through pi-type electrocyclic reactions. These findings are crucial for advancing catalytic applications involving titanium.
ACCOUNTS OF CHEMICAL RESEARCH
(2021)
Article
Chemistry, Multidisciplinary
Michael T. Davenport, Justin K. Kirkland, Daniel H. Ess
Summary: Reaction pathway selectivity in organometallic reactions involving spin state crossover is not controlled by transition states or minimum energy crossing points (MECPs), but rather by the dynamic motion during reactive collisions. Quasiclassical trajectories of single spin state and mixed spin state show nonstatistical intermediates and determine the selectivity between C-H insertion and π-coordination pathways. This dynamic-dependent product outcome provides a new selectivity model for organometallic reactions with spin crossover.
Article
Chemistry, Organic
Yolanda Navarro, Jesus Garcia Lopez, Maria Jose Iglesias, Fernando Lopez Ortiz
Summary: Through a ligand-free domino copper(I)-catalyzed azide-alkyne-azide process, 1,4-(disubstituted)-5-triazenyl-1,2,3-triazoles were synthesized successfully, and the crucial role of Cu-chelation in the interception of the intermediate by the azide was revealed through DFT calculations and X-ray diffraction analysis.
Article
Chemistry, Physical
Zhenzhen Wang, Xiaomei Shen, Xingfa Gao
Summary: Using density functional theory calculations, the study reveals the crucial role of oxygen vacancies in nanoceria catalysis and the dependence of nanoceria activity on the presence of oxygen vacancies. The results help explain the enzyme-like catalytic activities of nanoceria and may guide the future design of nanoceria-based enzyme mimics.
JOURNAL OF PHYSICAL CHEMISTRY C
(2021)
Article
Multidisciplinary Sciences
Zhenzhen Wang, Jiangjiexing Wu, Jia-Jia Zheng, Xiaomei Shen, Liang Yan, Hui Wei, Xingfa Gao, Yuliang Zhao
Summary: The study uses density functional theory calculations to investigate the principles behind the SOD-like catalytic activity of nanomaterials, proposing energy level and adsorption energy principles for quantitatively describing the activity. These principles were validated through experiments on metal-organic frameworks and can be easily implemented in computer programs for screening NMs with intrinsic SOD-like activity. A general predicting theory for superoxide-dismutase mimicking nanomaterials is currently lacking.
NATURE COMMUNICATIONS
(2021)
Review
Chemistry, Multidisciplinary
Xiaomei Shen, Zhenzhen Wang, Xuejiao J. Gao, Xingfa Gao
Summary: Nanozymes are inorganic nanomaterials with enzyme-like catalytic activities. The research on nanozymes is a hot topic in interdisciplinary science involving materials, chemistry, and biology. DFT calculations have played an increasingly important role in exploring the mechanisms and kinetics of nanozymes by providing atomistic-level insights into the microscopic processes. This review summarizes the research progress and focuses on the computational studies that complement experimental findings and promote the understanding of nanozyme mechanisms and kinetics.
ADVANCED MATERIALS
(2023)
Article
Multidisciplinary Sciences
Wenhui Gao, Jiuyang He, Lei Chen, Xiangqin Meng, Yana Ma, Liangliang Cheng, Kangsheng Tu, Xingfa Gao, Cui Liu, Mingzhen Zhang, Kelong Fan, Dai-Wen Pang, Xiyun Yan
Summary: We report a carbon dot (C-dot) superoxide dismutase (SOD) nanozyme with a catalytic activity comparable to that of natural enzymes. The SOD-like activity of C-dot nanozyme relies on specific chemical modifications and conjugated carbonyl groups for binding and electron transfer. Furthermore, the C-dot SOD nanozymes exhibit intrinsic targeting ability to oxidation-damaged cells and effectively protect neuron cells in the ischemic stroke mouse model.
NATURE COMMUNICATIONS
(2023)
Article
Chemistry, Physical
Qiao-Zhi Li, Huizhen Fan, Zhenzhen Wang, Jia-Jia Zheng, Kelong Fan, Xiyun Yan, Xingfa Gao
Summary: Currently, the research on catalysts that catalytically cut phos-phoester bonds using nanomaterials (NMs) is mainly limited to NMs consisting of high-valent metal ions, and a universal theory guiding the discovery of such NM catalysts is still lacking. This study investigates the mechanisms, kinetics, activity descriptors, and theoretical models for predicting the catalytic activities of arbitrary metal and metal-oxide NMs through density functional theory calculations and experiments. The results provide a systematic understanding of previously reported NM catalysts and theoretical guidelines for further optimization and screening of these catalysts.
Article
Engineering, Biomedical
Xuejiao J. Gao, Jun Yan, Jia-Jia Zheng, Shengliang Zhong, Xingfa Gao
Summary: In this study, a method for predicting the catalytic activities of materials towards tumor therapy was developed. This method combines adsorption-energy-based descriptors and criteria with density functional theory calculations and machine learning models. The method allows for efficient screening of 2D materials for catalytic therapy and will greatly contribute to the development of catalytic nanomaterials for medical applications.
ADVANCED HEALTHCARE MATERIALS
(2023)
Article
Chemistry, Multidisciplinary
Huizhen Fan, Jiajia Zheng, Jiaying Xie, Juewen Liu, Xingfa Gao, Xiyun Yan, Kelong Fan, Lizeng Gao
Summary: Nanozymes have great potential as alternatives to natural enzymes, but their practical use is limited by their low catalytic activity compared to natural enzymes. This study employed a surface engineering strategy using charge-transferrable ligands, such as polystyrene sulfonate (PSS), to improve the specific activity of Ru nanozymes. The modified Ru nanozyme exhibited a peroxidase-like specific activity double that of horseradish peroxidase. The modified Ru-peroxidase nanozyme was successfully used to develop an immunoassay with significantly increased detection sensitivity compared to traditional enzyme-linked immunosorbent assay.
ADVANCED MATERIALS
(2023)
Article
Chemistry, Multidisciplinary
Guolong Xing, Jingjuan Liu, Yi Zhou, Shuai Fu, Jia-Jia Zheng, Xi Su, Xingfa Gao, Osamu Terasaki, Mischa Bonn, Hai I. Wang, Long Chen
Summary: Conductive metal-organic frameworks (c-MOFs) with excellent electrical conductivities and charge transport properties were synthesized using contorted hexabenzocoronene (c-HBC) derivatives as nonplanar and highly soluble ligands. Three c-MOFs with different geometries and packing modes were obtained, among which c-HBC-12O-Cu exhibited the highest intrinsic electrical conductivity and all c-HBC-based c-MOFs showed high charge carrier mobilities. This work provides a systematic and modular approach to enhance the structure and charge transport properties of c-MOFs using nonplanar and highly soluble ligands.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2023)
Article
Multidisciplinary Sciences
Xuejing Cui, Xiaoyu Wang, Xueling Chang, Lin Bao, Junguang Wu, Zhiqiang Tan, Jinmei Chen, Jiayang Li, Xingfa Gao, Pu Chun Ke, Chunying Chen, Catherine Murphy
Summary: Carbon-based nanomaterials (CNMs) have been found in humans, and their integration into the endogenous carbon flow through the gut microbiota has been uncovered. The gut microbiota ferments CNMs, incorporating inorganic carbon into organic butyrate. Butyrate-producing bacteria prefer CNMs as their carbon source, and excessive butyrate derived from microbial CNMs fermentation affects the function of intestinal stem cells. This study highlights the need to assess the transformation of CNMs and their health risk via the gut-centric physiological and anatomical pathways.
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
(2023)
Article
Chemistry, Physical
Zhenzhen Wang, Huan Meng, Xuejiao J. Gao, Jia-Jia Zheng, Xingfa Gao
Summary: The Hammett equation is commonly used for theoretical modeling of the substituent effects on catalytic activities of metal-organic frameworks (MOFs). However, its application to MOF catalysts faces challenges due to unknown transferability of empirical parameters. In this study, a linker orbital energy model is proposed, which offers a simple way to estimate the remote electronic substituent effects on MOF catalysis and demonstrates its general applicability to MOFs based on extensive literature review. The model can be utilized for designing the catalytic activities of metal nodes in MOFs by manipulating the electronic properties of linkers and substituents.
NPJ COMPUTATIONAL MATERIALS
(2023)
Review
Chemistry, Multidisciplinary
Xuejiao J. Gao, Yuliang Zhao, Xingfa Gao
Summary: Developing biocompatible catalytic nanomaterials to target cancer reactive oxygen species (ROS) has provided a promising alternative chemotherapy strategy. Despite progress in synthesizing inorganic nanomaterials with potential therapeutic functions, the chemicobiological mechanisms underlying ROS-targeted catalysis and subsequent cancer therapeutic functions of nanomaterials remain elusive. This study proposes catalytic signal transduction theory to bridge the gap between catalytic activities and medical functions of inorganic nanomaterials, providing theoretical tools for the design and screening of candidate nanomaterials for cancer therapy.
ACCOUNTS OF CHEMICAL RESEARCH
(2023)
Article
Chemistry, Multidisciplinary
Wei Xu, Jia-Jia Zheng, Yu-An Li, Xingfa Gao, Xiaobo Ji, Yi-Ge Zhou
Summary: The electrochemical processes of individual PB particles were investigated using nano-impact electrochemistry, revealing the kinetic mechanism of each oxidation/reduction reaction through theoretical simulation. The partially contradictory conclusion between single-particle analysis and the ensemble-averaged measurement was discussed. These findings contribute to a better understanding of the electrochemical processes of cathode materials with multiple redox centers and facilitate the development of effective strategies to optimize these materials.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Multidisciplinary
Cong Liu, Lin Gui, Jia-Jia Zheng, Yong-Qiang Xu, Benli Song, Li Yi, Yijiang Jia, Ayijiang Taledaohan, Yuji Wang, Xingfa Gao, Zeng-Ying Qiao, Hao Wang, Zhiyong Tang
Summary: Metaloxide nanozymes have emerged as the most promising candidates for treating oxidative stress-mediated disorders, but their current efficacy is insufficient. This study introduces an intrinsic strain-mediated ultrathin ceria nanoantioxidant, which exhibits enhanced SOD-mimetic and total antioxidant activities. In vivo experiments demonstrate that these ultrathin ceria nanoplates can significantly improve the treatment of ischemic stroke, outperforming the commonly used drug edaravone.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2023)
Article
Chemistry, Multidisciplinary
Shotaro Ito, Youichi Ishii, Kazuya Ishimura, Takuya Kuwabara
Summary: A new strategy for hyperconjugative antiaromatic compounds was proposed, with experimental and theoretical evidence supporting the hyperconjugative antiaromaticity of the newly designed compound.
CHEMICAL COMMUNICATIONS
(2021)
Article
Chemistry, Physical
Ramesh Kumar Chitumalla, Kiduk Kim, Xingfa Gao, Joonkyung Jang
Summary: The study reveals that catechol adheres onto a wet graphite surface mainly through pi-pi stacking and hydrogen bonds with water molecules, with significant charge transfer observed. These findings contribute to understanding the water-resistant adhesion mechanism of catechol on different types of surfaces.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2021)
