Article
Chemistry, Multidisciplinary
Matthew J. J. Genzink, Matthew D. D. Rossler, Herman Recendiz, Tehshik P. P. Yoon
Summary: Chiral acid catalysts are shown to promote highly selective visible-light photocycloadditions, leading to the synthesis of truxinate natural products. This general approach allows for the efficient synthesis of dimeric and pseudodimeric cyclobutane natural products with excellent enantioselectivity.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2023)
Article
Chemistry, Physical
Jian-Hua Liu, Qing Zhou, Yao Lin, Zhu-Lian Wu, Tian Cai, Wei Wen, Yan-Min Huang, Qi-Xiang Guo
Summary: In this study, a highly efficient atom-economic asymmetric alpha-allylation method using chiral-aldehyde/palladium catalyst was reported. This method enables the asymmetric alpha-allylation of different 1,3-dienes and allenes with N-unprotected amino acid esters, leading to the synthesis of alpha,alpha-disubstituted chiral alpha-amino acid esters with high efficiency, good yields, and stereoselectivities. No N-allylation byproducts were observed in these reactions. Two reaction models were proposed based on mechanistic control experiments. Overall, this work demonstrates a new approach for preparing structurally diverse chiral amino acids and provides insights for developing chiral-aldehyde catalytic systems.
Article
Chemistry, Multidisciplinary
Hoimin Jung, Mannkyu Hong, Marianna Marchini, Marco Villa, Philipp S. Steinlandt, Xiaoqiang Huang, Marcel Hemming, Eric Meggers, Paola Ceroni, Jiyong Park, Mu-Hyun Baik
Summary: The mechanism of [2 + 2] cycloadditions activated by visible light and catalyzed by bis-cyclometalated Rh(iii) and Ir(iii) photocatalysts was investigated. Experimental observations show that the Rh-based photocatalyst produces excellent yield and enantioselectivity, whereas the Ir-photocatalyst yields racemates. Two different mechanistic features were found to compete with each other.
Article
Chemistry, Physical
Joshua Clarke, Youngran Seo, Michel R. Gagne, Trandon A. Bender
Summary: This perspective discusses the key lessons learned from a program aiming to selectively deoxygenate cellulose-derived carbohydrates, with a focus on noneliminative mechanisms and the use of fluoroaryl borane catalysts. The control of substrate and catalyst over the deoxygenation process is crucial, and the lessons from this catalysis program can be applied to other important problems in catalysis and selectivity.
Article
Chemistry, Multidisciplinary
Yating Dai, Shuangshuang Liang, Guangkuo Zeng, Hongchun Huang, Xiaowei Zhao, Shanshan Cao, Zhiyong Jiang
Summary: This article presents a novel protocol based on chiral hydrogen-bonding catalytic strategy for converting electron-rich olefins to acceptors, and successfully carries out asymmetric photocycloadditions. The method is effective for electron-neutral olefins and allows the construction of all-carbon quaternary stereocentres with structurally similar aryl substituents.
Article
Chemistry, Organic
Elizabeth D. Heafner, Xuechun Lin, Alexa H. Connors, Hanyu Zhong, R. Joseph Coyle, Yiqi Liu, C. Wade Downey
Summary: This study demonstrates that ketones and related substrate classes can undergo enol silane formation and allylation in the presence of TMSOTf and triethylamine, resulting in high yields. Additionally, aldehydes, esters, and thioesters can also serve as enol silane precursors. The regioselectivity of the reaction is dependent on the electronic and steric properties of the substituents when unsymmetrical allyl cations are employed.
SYNTHESIS-STUTTGART
(2023)
Article
Chemistry, Physical
Christopher C. McAtee, Daniel J. Nasrallah, Ho Ryu, Michael R. Gatazka, Rory C. McAtee, Mu-Hyun Baik, Corinna S. Schindler
Summary: We describe a regioselective Lewis-acid-catalyzed method for the synthesis of highly functionalized cyclopentadienes incorporating diverse subunits. Insightful studies suggest that the mechanism involves Lewis-acid-catalyzed cycloadditions followed by stepwise oxetane fragmentation, resulting in the formation of functionalized cyclopentadienes. This work provides new insights into the design of catalytic carbonyl-olefin metathesis reactions.
Article
Chemistry, Multidisciplinary
Lydia Cox, Yuxiang Zhu, Philip J. Smith, Kirsten E. Christensen, Mireia Sidera Portela, Timothy J. Donohoe
Summary: A Ti(Oi-Pr)(4)-promoted 5- or 6-endo-trig cyclization for the synthesis of nitrogen heterocycles is presented. The use of HFIP as a key solvent enables the stereoselective formation of di- and tri-substituted pyrrolidines and piperidines while simultaneously forming a new C-C bond. The process involves the generation of a cationic intermediate from an allylic or benzylic alcohol and leads to the simultaneous generation of both a C-C and a C-N bond in a single step. Notably, different substituents on a nucleophilic amine yield either 2,3-trans- or 2,3-cis-substituted heterocycles. Lastly, enantiopure products can be obtained by using readily available enantiopure acyclic starting materials.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Chemistry, Multidisciplinary
Ana M. Martinez-Gualda, Pablo Domingo-Legarda, Thomas Rigotti, Sergio Diaz-Tendero, Alberto Fraile, Jose Aleman
Summary: The asymmetric synthesis of chiral polycyclic ethers is achieved through an intramolecular [2+2] photocycloaddition, utilizing a photocatalytically active iminium ion-based charge transfer complex under visible light irradiation. This method enables stereocontrolled [2+2] photocycloaddition, yielding tricyclic products with good enantiomeric ratios.
CHEMICAL COMMUNICATIONS
(2021)
Review
Chemistry, Inorganic & Nuclear
Pierre de Fremont, Nicolas Adet, Jordan Parmentier, Xuejuan Xu, Beatrice Jacques, Samuel Dagorne
Summary: This review comprehensively summarizes the synthesis, structure, and catalytic applications of group 12 metal (Zn, Cd, Hg) organocations reported since 2010. With appropriate ligand design and straightforward synthetic methodologies, various classes of stable and tunable Zn-II cationic complexes have been developed as potentially potent Lewis acids with catalytic activity. These recently developed Zn-II organocations have been extensively used as catalysts for important catalytic processes such as hydro-elementation and C-H functionalization of unsaturated small molecules. However, research contributions on Cd-II and Hg-II organocations are currently limited due to their toxicity.
COORDINATION CHEMISTRY REVIEWS
(2022)
Article
Chemistry, Multidisciplinary
Hiroyuki Miyamura, Shu Kobayashi
Summary: This paper describes the development of cooperative and synergistic catalyst systems of heterogeneous Rh-Pt bimetallic nanoparticle catalysts, Rh-Pt/DMPSi-Al2O3, and Sc(OTf)(3) in the liquid phase for the hydrogenation of arenes under very mild conditions. The cooperative activation achieved significant rate acceleration and successful hydrogenation of challenging substrates with strong electron-donating groups and sterically hindered substituents was demonstrated.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Chemistry, Physical
Francisco de Azambuja, Jille Lenie, Tatjana N. Parac-Vogt
Summary: Inorganic clusters, specifically polyoxometalates (POMs), can serve as effective ligands for Hf(IV) Lewis acid metals in homogeneous metal catalysis. The interplay between the dielectric constant of the medium and the ligand structure is crucial for optimizing catalytic activity and promoting efficient amide bond formation. Changes in the dielectric constant can significantly impact the performance of the catalyst, highlighting the importance of understanding the relationship between medium properties and catalyst reactivity.
Article
Chemistry, Multidisciplinary
Wen-Xuan Cao, Lei Zhu, Yiyi He, Run Wang, Ming Liu, Qin Ouyang, Qing Xiao
Summary: The first aryne insertions into the carbon-iodine bond of heteroaryl iodides have been achieved. This novel reaction provides an efficient pathway for the synthesis of valuable building blocks 2-iodoheterobiaryls with excellent regioselectivity by reacting heteroaryl iodides and o-silylaryl triflates. The copper(I) catalyst, which contains a N-heterocyclic carbene (NHC) ligand, is essential for the reaction. Control reactions and DFT calculations suggest that the coordination of copper, acting as a Lewis acid, with nitrogen atoms of heteroaryl iodides mediates the aryne insertions into heteroaryl carbon-iodine bonds.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Physical
Qinyi Li, Xinmin Liu, Weiyu Shi
Summary: This study confirms that the strong electric field and orbital asymmetric hybridization at charged clay surface substantially enhance Lewis acid-base reactions between Cu2+, Ca2+, Mg2+ and surface O. Infrared spectral analyses reveal changes in reaction intensity, highlighting the significance of these factors in clay catalyst design.
APPLIED SURFACE SCIENCE
(2022)
Article
Chemistry, Organic
Aleksandr E. Rubtsov, Andrei V. Malkov
Summary: Asymmetric crotylation has become an important tool in organic synthesis for stereoselective construction of carbon skeletons. The use of organometallic reagents based on silicon and boron, as well as the development of new chiral Lewis base catalysts, are highlighted in this account. Additionally, a novel protocol for kinetic resolution of racemic secondary allylboronates has been discussed in the context of setting up stereogenic centers.
Article
Chemistry, Physical
Dai Wei-Li, Jin Bi, Luo Sheng-Lian, Luo Xu-Biao, Tu Xin-Man, Au Chak-Tong
APPLIED CATALYSIS A-GENERAL
(2014)
Article
Chemistry, Physical
Jian-Ping Zou, Si-Liang Lei, Jian Yu, Sheng-Lian Luo, Xu-Biao Luo, Xing-Hua Tang, Wei-Li Dai, Jing Sun, Guo-Cong Guo, Chak-Tong Au
APPLIED CATALYSIS B-ENVIRONMENTAL
(2014)
Article
Chemistry, Physical
Bin Guo, Fang Deng, Yu Zhao, Xubiao Luo, Shenglian Luo, Chaktong Au
APPLIED SURFACE SCIENCE
(2014)
Article
Chemistry, Physical
Yi-Qiang Deng, Teng Zhang, Chak-Tong Au, Shuang-Feng Yin
CATALYSIS COMMUNICATIONS
(2014)
Article
Chemistry, Applied
Chuan Shi, Shaohua Zhang, Xiaosong Li, Anjie Zhang, Ming Shi, Yongjun Zhu, Jieshan Qiu, Chaktong Au
Article
Engineering, Environmental
Teng Zhang, Yi-Qiang Deng, Wei-Fang Zhou, Chak-Tong Au, Shuang-Feng Yin
CHEMICAL ENGINEERING JOURNAL
(2014)
Article
Physics, Multidisciplinary
Yang Zai-Xing, Zhong Wei, Au Chak-Tong, Du You-Wei
Review
Physics, Multidisciplinary
Zhong Wei, Au Chak-Tong, Du You-Wei
Article
Chemistry, Multidisciplinary
Junfeng Zhang, Xinzhen Feng, Yuling Zhao, Weijie Ji, Chak-Tong Au
JOURNAL OF INDUSTRIAL AND ENGINEERING CHEMISTRY
(2014)
Article
Chemistry, Organic
Xiuling Chen, Tieqiao Chen, Yongbo Zhou, Chak-Tong Au, Li-Biao Han, Shuang-Feng Yin
ORGANIC & BIOMOLECULAR CHEMISTRY
(2014)
Article
Chemistry, Physical
Dai Wei-Li, Jin Bi, Luo Sheng-Lian, Luo Xu-Biao, Tu Xin-Man, Au Chak-Tong
CATALYSIS SCIENCE & TECHNOLOGY
(2014)
Article
Chemistry, Multidisciplinary
Jin Zhao, Jun Xie, Chak-Tong Au, Shuang-Feng Yin
Article
Nanoscience & Nanotechnology
Xuemin He, Wei Zhong, Chak-Tong Au, Youwei Du
NANOSCALE RESEARCH LETTERS
(2013)
Article
Nanoscience & Nanotechnology
Qian Ding, Xueyin Song, Xiujuan Yao, Xiaosi Qi, Chak-Tong Au, Wei Zhong, Youwei Du
NANOSCALE RESEARCH LETTERS
(2013)
Article
Chemistry, Applied
Jun Ni, Zhenni Tan, Qianjin Sai, Jie Zhu, Xiuyun Wang, Bingyu Lin, Jianxin Lin, Chak-tong Au, Lilong Jiang
Summary: A new strategy has been developed to confine Ru and/or Co nanoparticles in the channels of N-doped carbon using benzoic acid, which results in a catalyst with high resistance against Ru sintering, showing excellent activity and long term stability for NH3 synthesis. This study provides a new avenue for simple fabrication of precious-metal-based catalysts that are highly resistant against sintering, specifically suitable for low-temperature synthesis of ammonia with outstanding efficiency.
JOURNAL OF ENERGY CHEMISTRY
(2021)
Article
Chemistry, Organic
Geeta Devi Yadav, Pooja Chaudhary, Balaram Pani, Surendra Singh
Summary: Chiral transition metal complexes with privileged ligands are efficient catalysts for various asymmetric organic transformations. Transition metal complexes of C1-symmetric pyrrolidine-based ligands have been widely used in asymmetric organic reactions. However, a comprehensive review article on the transition metal complexes of chiral C1-symmetric pyrrolidine-based ligands derived from (L)-proline has not been published.
TETRAHEDRON LETTERS
(2024)
