Article
Chemistry, Inorganic & Nuclear
Lu Dong, Linke Yu, Xueli Sun, Xiongkai Tang, Xuexin You, Jiaqi Tang, Zi-Ang Nan, Dongxu Cao, Yanyuan Jia, Simin Li, Fengyu Li, Shuo Guo, Hui Shen
Summary: We report a stable gold-copper alloy nanocluster with high catalytic performance. The nanocluster exhibits high thermal stability and contains rich uncoordinated copper sites, which contribute to its extremely high catalytic activity in C-O coupling reactions. This finding is of great significance for understanding the underlying rationale of ligand-functionalized metal nanocatalysts.
INORGANIC CHEMISTRY FRONTIERS
(2023)
Article
Chemistry, Physical
Takumi Koshikawa, Juntaro Nogami, Yuki Nagashima, Ken Tanaka
Summary: This paper reports the application of Pt(II) and Au(I) catalysts in inter- and intramolecular cascade [4+2] annulation reactions, as well as the mechanistic study of the reaction products. In the Pt(II)-catalyzed reaction, annulation occurs between two alkenes via two benzopyrylium intermediates. In the Au(I)-catalyzed reaction, annulation takes place between one alkene and benzopyrylium and quinodimethane intermediates. In addition, the Au(I)-catalyzed reaction of indole-yne-carbonyls with one alkene proceeds through benzopyrylium rather than quinodimethane or carbocation intermediates, as supported by DFT calculations.
Article
Chemistry, Organic
Qian Xiao, Maojian Lu, Yinglan Deng, Jing-Xin Jian, Qing-Xiao Tong, Jian-Ji Zhong
Summary: This simple and mild photoredox catalytic approach allows for the high regioselective synthesis of difluoroalkylated dioxodibenzothiazepines, without the use of transition-metal catalysts and the potential drawbacks associated with their removal process. The method demonstrates practicality through its use of commercially available and inexpensive CF precursors, wide substrate scope, and mild reaction conditions.
Article
Chemistry, Organic
Yunliang Yu, Nazarii Sabat, Meriem Daghmoum, Zhenhao Zhang, Pascal Retailleau, Gilles Frison, Angela Marinetti, Xavier Guinchard
Summary: Enantioselective tandem cycloisomerization/addition reactions of 2-alkynyl enones with 1- and 2-naphthols were investigated using gold(I) catalysts featuring hybrid phosphine-phosphoric acid chiral ligands, based on the tethered counterion-directed catalysis strategy. The reactions proceeded at low catalyst loading (0.2-1 mol%) without the need for silver additives, and the naphthols acted as both O- and C-nucleophiles, resulting in the formation of addition products with high enantioselectivity. The mechanism of these reactions was elucidated by DFT calculations.
ORGANIC CHEMISTRY FRONTIERS
(2023)
Article
Chemistry, Organic
Huaxin Zhang, Yongge Xiong, Jiang Bai, Ruchun Yang, Xian-Rong Song, Qiang Xiao
Summary: We introduce a highly efficient and practical method for synthesizing gem-dibromo 1,3-oxazines through 6-endo-dig cyclization of propargylic amides, using N-bromosuccinimide (NBS) as an electrophilic source. This metal-free reaction can be carried out under mild conditions, showing good compatibility with various functional groups and providing excellent yields of the desired products. Mechanistic studies indicate that the reaction proceeds through a double electrophilic attack of NBS on the propargylic amide substrate.
ORGANIC & BIOMOLECULAR CHEMISTRY
(2023)
Review
Chemistry, Multidisciplinary
T. Ghosh, S. Bhakta
Summary: This review summarizes recent developments (from 2006 to 2022) in the synthesis of important and efficient carbo- and heterocycles using gold-catalyzed cascade protocols. The methodologies discussed in this paper involve controlling selectivity, cost-effectiveness, and ease of product formation through the ligand, counter anion, catalyst, substrate, and reaction conditions. Gold-catalyzed cascade reactions encompass different strategies, including cyclization, hydroarylation, intermolecular and intramolecular cascade reactions, and more. This type of reaction is valuable for the synthesis of spiro, fused, bridged carbo- and heterocycles.
Article
Chemistry, Physical
Calton J. Kong, Emily L. Warren, Ann L. Greenaway, Rajiv Ramanujam Prabhakar, Adele C. Tamboli, Joel W. Ager
Summary: Cascade photoelectrocatalysis involves coupling different CO2 reduction catalysts to different branches to enhance the selectivity of solar-driven CO2 reduction. Design principles include tuning photocurrents and photovoltages to facilitate the target reaction.
SUSTAINABLE ENERGY & FUELS
(2021)
Article
Multidisciplinary Sciences
Shiquan Gao, Chen Wang, Junfeng Yang, Junliang Zhang
Summary: In this study, an enantioselective intramolecular reductive coupling of enynes was achieved via the combination of electrochemistry and cobalt catalysis. The transition-metal catalyzed asymmetric cyclization of 1,6-enynes has been widely used for the construction of carbocycles and heterocycles, but examples under electrochemical conditions are rare. We report a Co-catalyzed enantioselective intramolecular reductive coupling of enynes using H2O as the hydride source, which provides good yields with high regio- and enantioselectivities. This study represents a rare progress on the cobalt-catalyzed enantioselective transformation via electrochemistry with a general substrate scope, and DFT studies suggest the possible reaction pathways.
NATURE COMMUNICATIONS
(2023)
Article
Chemistry, Physical
Yang Gao, Simin Yang, Yanping Huo, Qian Chen, Xianwei Li, Xiao-Qiang Hu
Summary: A highly efficient NiH catalytic system was developed for the selective hydroamination of alkynes, leading to structurally diverse quinolines. This method is applicable to a wide range of alkynes and has shown utility in the functionalization of natural products and the synthesis of complex molecules. Preliminary mechanistic experiments suggest an alkenylnickel-mediated alkyne hydroamination and intramolecular cyclization of enamine intermediates.
Review
Chemistry, Organic
Cui Xiaoyuan, Zhou Feng, Wu Haihong, Zhou Jian
Summary: Cooperative catalysis is an effective strategy to improve the efficiency and selectivity of organic reactions. Combining chiral amines and gold(I) catalysts can achieve asymmetric tandem reactions, allowing the construction of complex chiral compounds.
CHINESE JOURNAL OF ORGANIC CHEMISTRY
(2022)
Review
Chemistry, Applied
Krishna Biswas, Aniruddha Das, Venkataraman Ganesh
Summary: Organophosphorus catalysis has become a robust platform for introducing boron and silicon functionalities into organic substrates, providing efficient synthetic methodologies. Phosphorus compounds efficiently catalyze various reactions such as hydroboration and silylation in different organic substrates, with the classification of nucleophilic, electrophilic, and biphilic phosphorus catalysts.
ADVANCED SYNTHESIS & CATALYSIS
(2021)
Article
Chemistry, Organic
Huaxin Zhang, Yongge Xiong, Mu-Jia Luo, Ruchun Yang, Jiang Bai, Xian-Rong Song, Qiang Xiao
Summary: Here, a novel and sustainable electrochemically driven oxidative 5-exo-dig radical cyclization of N-propargylbenzamides with alcohols is described, providing a convenient method for the synthesis of structurally diverse oxazole ketals in moderate to good yields. This protocol is achieved under mild conditions in an undivided cell without the need for external transition-metal catalysts, chemical oxidants, and ketalization acids, and exhibits scalability, broad substrate scope, and excellent functional group compatibility. Mechanistic studies reveal that the reaction proceeds via a nucleophilic substitution process rather than ketalization.
ORGANIC CHEMISTRY FRONTIERS
(2023)
Article
Chemistry, Multidisciplinary
David M. Upp, Rui Huang, Ying Li, Max J. Bultman, Benoit Roux, Jared C. Lewis
Summary: Artificial metalloenzymes (ArMs) were engineered to catalyze diazo cross-coupling resulting in high enantioselectivity alkene reduction to alkane in a one-pot cascade reaction. Directed evolution improved reaction yields and selectivities for various substrates. Molecular dynamics simulations of ArM variants were used to understand the structural role of the cofactor on ArM conformational dynamics, highlighting the ability of ArMs to control both catalyst stereoselectivity and chemoselectivity in complex media.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2021)
Article
Chemistry, Organic
Paula Fernandez-Canelas, Pablo Barrio, Jose M. Gonzalez
Summary: This article provides an overview of the reactivity of Haloalkynes under gold catalysis, with particular attention to intramolecular reactions involving halide-shift.
TETRAHEDRON LETTERS
(2022)
Article
Chemistry, Organic
Cunbo Wei, Jiawen Wu, Lizhu Zhang, Zhonghua Xia
Summary: A highly selective synthesis of Z-alkenyl indoles was developed by adding indoles to haloalkynes using a gold catalyst and a cocatalyst, resulting in high yields at room temperature.
