Article
Chemistry, Organic
Xiaoqin Ning, Yongke Chen, Fangdong Hu, Ying Xia
Summary: This study presents the palladium-catalyzed cross-coupling reactions of cyclobutanone-derived N-sulfonylhydrazones with aryl or benzyl halides, demonstrating that the metal carbene process and beta-hydride elimination can occur smoothly in strained ring systems to yield structurally diverse products. The preliminary success in asymmetric carbene coupling reactions in strained ring systems offers a promising route for the synthesis of enantioenriched four-membered-ring molecules.
Article
Chemistry, Multidisciplinary
Maorui Wang, Chengqian Zhang, Chenggang Ci, Huanfeng Jiang, Pierre. H. Dixneuf, Min Zhang
Summary: Despite the challenges, we have successfully developed a room temperature approach for the direct construction of alpha-hydroxyalkyl cyclic amines through the strategy of electroreductive alpha-hydroxyalkylation. This method offers a broad substrate scope, simplicity in operation, high chemoselectivity, and does not require pressurized H2 gas or transition metal catalysts. The activation of reactants by the zinc ion generated from anode oxidation plays a crucial role in this transformation. This strategy, combined with substrate activation by Lewis acids, is expected to lead to the development of more useful transformations.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2023)
Article
Chemistry, Multidisciplinary
Yuri Saito, Jun Kikuchi, Chen Wang, Naohiko Yoshikai
Summary: We report the design and development of Co/Al and Co/Mg bimetallic catalysts supported by a phosphine/secondary phosphine oxide (PSPO) bifunctional ligand for the selective C-H alkenylation of nitrogen-containing heteroarenes with alkynes. These catalysts enable the alkenylation of pyridine, pyridone, and imidazo[1,2-a]pyridine derivatives at the C-H site proximal to the Lewis basic nitrogen or oxygen atom, with a selectivity profile distinct from previously developed cobalt-diphosphine/aluminum catalyst. The alkenylated products were obtained in moderate to good yields using various heterocycles and differently substituted internal alkynes. Kinetic isotope effect experiments suggest the irreversibility of the C-H activation step, the relevance of which to the rate-limiting step depends on the reaction conditions. Density functional theory calculations indicate that ligand-to-ligand hydrogen transfer is the common mechanism of C-H activation.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Multidisciplinary
Wang Jiang, Xiuxiu Yang, Lin Lin, Chaoguo Yan, Yue Zhao, Minyan Wang, Zhuangzhi Shi
Summary: Metal-catalyzed C-H activation strategies provide an efficient approach for synthesis. In this study, visible-light-induced late-stage C-H activation was achieved using a single rhodium complex. The reaction offers advantages such as environmental friendliness and the utilization of inherent directing groups, providing a new platform for ligand design and preparation.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Organic
Pooja Y. Vemuri, Frederic W. Patureau
Summary: In this study, an unprecedented, simple and hetero-selective cross-dehydrogenative N-N coupling of amides and benzotriazoles using a hypervalent iodine species as the terminal oxidant was reported. The scope and mechanistic investigations of this reaction were discussed.
Article
Chemistry, Multidisciplinary
Ziyu Chen, Shiqun Wu, Jiayu Ma, Shinya Mine, Takashi Toyao, Masaya Matsuoka, Lingzhi Wang, Jinlong Zhang
Summary: In this study, an n-type doped photocatalyst for NOCM was successfully developed by introducing Nb into TiO2-SiO2 microarray, showing promising performance. Comparison with other n-type dopants like Mo, W, and Ta further confirmed the positive effect of n-type dopant on CH4 conversion. In contrast, the doping of p-type dopants had a less active influence in this process.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2021)
Article
Chemistry, Organic
Bholanath Garai, Molla Rahamat Ali, Rajib Mandal, Basker Sundararaju
Summary: This study demonstrates the C(8)-selective nucleophilic cascade cyclization of quinoline N-oxide with easily derived 1,6-enyne from phenol derivatives. Various quinoline N-oxide and alkynes are found to be suitable for producing a library of quinoline N-oxide tethered cis-hydrobenzofurans with high yields and excellent functional group tolerance. The utility of the protocol has been achieved through post-synthetic modification of the cyclized product. Mechanistic studies reveal a base-assisted internal electrophilic-type substitution (BIES)-type pathway for C-H bond activation, and electrospray ionization mass spectrometry (ESI-MS) analysis confirms the formation of a key five-membered cobaltacycle.
Article
Chemistry, Organic
Bholanath Garai, Molla Rahamat Ali, Rajib Mandal, Basker Sundararaju
Summary: This study demonstrates the C(8)-selective nucleophilic cascade cyclization of quinoline N-oxide with easily derived 1,6-enyne from phenol derivatives. Various quinoline N-oxide and alkynes are suitable for producing a library of quinoline N-oxide tethered cishydrobenzofurans with high yields and excellent functional group tolerance. The protocol's utility is achieved through post-synthetic modification of the cyclized product. Mechanistic studies suggest a base-assisted internal electrophilic-type substitution (BIES)-type pathway for C-H bond activation, and electrospray ionization mass spectrometry (ESI-MS) analysis confirms the formation of a key five-membered cobaltacycle.
Article
Chemistry, Multidisciplinary
Xiaoran Zhang, Xiaorong Zhu, Shuowen Bo, Chen Chen, Kai Cheng, Jianyun Zheng, Shuang Li, Xiaojin Tu, Wei Chen, Chao Xie, Xiaoxiao Wei, Dongdong Wang, Yingying Liu, Pinsong Chen, San Ping Jiang, Yafei Li, Qinghua Liu, Conggang Li, Shuangyin Wang
Summary: Electrocatalytic urea synthesis via coupling N-2 and CO2 offers an effective solution to address the energy crisis and reduce carbon emissions. Traditional methods face challenges in breaking N & EQUIV;N, resulting in low efficiencies for NH3 and urea synthesis. However, a new mechanism of elongating N & EQUIV;N allows for one-step C-N coupling, leading to high selectivity for urea synthesis.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Physical
Jiangjie Zhang, Jinni Shen, Dongmiao Li, Jinlin Long, Xiaochen Gao, Wenhui Feng, Shiying Zhang, Zizhong Zhang, Xuxu Wang, Weimin Yang
Summary: Metal-decorated oxide semiconductors are efficient photocatalysts for nonoxidative coupling of methane, but the detailed mechanism remains unknown. In this study, a series of noble metal-decorated oxides were investigated for methane coupling. It was found that the active sites for H abstraction and C-C coupling of CH4 were spatially separated. Noble metals, especially Ag, significantly decreased the energy barrier and promoted C-C coupling, leading to high CH4 conversion and selectivity. This work provides molecular-level insight into the CH4 coupling mechanism on metal-decorated photocatalysts.
Review
Chemistry, Applied
Dong Wang, Laurent Desaubry, Gaoyu Li, Mindong Huang, Shixin Zheng
Summary: Recent progress has been made in the direct C-H functionalization of azines, but limitations still exist. In contrast, C2-functionalized pyridines and quinolines can be easily synthesized under appropriate activation conditions.
ADVANCED SYNTHESIS & CATALYSIS
(2021)
Article
Chemistry, Physical
Ya-Ya Wang, Xun-Lei Ding, Joseph Israel Gurti, Yan Chen, Wei Li, Xin Wang, Wen-Jie Wang, Jia-Jun Deng
Summary: Adsorption and activation of N-2 on Mo6S8q_V-x clusters are influenced by metal types, N-2 coordination modes, and charge states of the clusters. Particularly, anionic Mo6S8-_V-2 clusters show remarkable ability to fix and activate N-2 through coordinated interaction with V atoms.
Review
Chemistry, Applied
Roman S. Malykhin, Alexey Yu Sukhorukov
Summary: The review summarizes recent advances in the synthesis of C2-halogenated nitrogen heterocycles via nucleophilic halogenation of corresponding N-oxides and its application in pharmaceutical synthesis. It provides a practical guide based on extensive literature analysis to help practitioners choose optimal reagents/conditions for nucleophilic halogenation of N-heterocycles of different types. The bibliography contains 199 references.
ADVANCED SYNTHESIS & CATALYSIS
(2021)
Article
Chemistry, Applied
Mai Yanagawa, Shingo Harada, Shumpei Hirose, Tetsuhiro Nemoto
Summary: The study developed a rhodium-catalyzed C-H functionalization reaction for synthesizing 2,3-fused indole variants using an alpha,beta-unsaturated enone as a directing group and electrophile. This annulation enabled the rapid assembly of valuable hydrocarbazolones from readily available indoles, and computational investigations were conducted to elucidate the reaction pathway and site-selectivity.
ADVANCED SYNTHESIS & CATALYSIS
(2021)
Article
Chemistry, Multidisciplinary
Alexander Purtsas, Marco Rosenkranz, Evgenia Dmitrieva, Olga Kataeva, Hans-Joachim Knoelker
Summary: In this paper, the oxygenation and amination reactions of tertiary arylamines are described. The key steps of these coupling reactions involve iron-catalyzed oxidative C-O or C-N bond formation, which typically provide the desired products in high yields and with excellent regioselectivity. These transformations are carried out using hexadecafluorophthalocyanine-iron(II) (FePcF16) as catalyst, with the presence of an acid or base additive, and only require ambient air as the oxidant.
CHEMISTRY-A EUROPEAN JOURNAL
(2022)
Article
Chemistry, Physical
Liang Ge, Huan Zhou, Mong-Feng Chiou, Heming Jiang, Wujun Jian, Changqing Ye, Xiaoyan Li, Xiaotao Zhu, Haigen Xiong, Yajun Li, Lijuan Song, Xinhao Zhang, Hongli Bao
Summary: The study reports a radical asymmetric carboazidation of olefins via an iron-catalysed group transfer mechanism, providing valuable chiral halogenated organoazides from inexpensive industrial chemical feedstocks. The method is supported by mechanistic studies and is expected to inspire further development of enantioselective radical reactions.
Article
Chemistry, Multidisciplinary
Linxing Zhang, Kun An, Yi Wang, Yun-Dong Wu, Xinhao Zhang, Zhi-Xiang Yu, Wei He
Summary: This study elucidates the reaction pathway and a more efficient catalyst for C-H silylation through a combination of computational and experimental methods, providing a foundation for further research.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2021)
Article
Chemistry, Multidisciplinary
Kai Wang, Ziye Liu, Guangyang Xu, Ying Shao, Shengbiao Tang, Ping Chen, Xinhao Zhang, Jiangtao Sun
Summary: Asymmetric carbene insertion reactions are crucial for constructing carbon-heteroatom bonds, but high enantioselectivity typically requires the use of donor-acceptor diazo compounds with an ester group. This study presents the first chemo and enantioselective formal N-H insertion of 2-pyridones using enynones as donor-donor carbene precursors, with DFT calculations revealing an unprecedented enantioselective 1,4-proton transfer from O to C. The rhodium catalyst's chiral pocket, along with steric repulsion and pi-pi interactions of the propeller ligand, play essential roles in determining the selectivities.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2021)
Article
Engineering, Environmental
Bei Ye, Ziye Liu, Xiaoqin Zhu, Hanjing Wu, Zifan Liang, Wenlong Wang, Qianyuan Wu, Hongying Hu, Xinhao Zhang
Summary: Chlorination is a widely used method for water disinfection, and ammonia/chlorine co-exposure can have a synergistic effect on the degradation of atrazine (ATZ), involving the formation of hydroxyl radicals (OH) and reactive chlorine species.
CHEMICAL ENGINEERING JOURNAL
(2021)
Article
Chemistry, Organic
Zhanfeng Hou, Yuena Wang, Chuan Wan, Lijuan Song, Rui Wang, Xiaochun Guo, Dongyan Yang, Yaping Zhang, Xuan Qin, Ziyuan Zhou, Xinhao Zhang, Feng Yin, Zigang Li
Summary: In this study, the first Cu-free click reaction between alkynyl sulfonium and azide at ambient temperatures in aqueous media is reported. DFT computations reveal that the sulfonium group plays a key role in enhancing reactivity by stabilizing LUMO+1 and influencing the charge distribution of the triple bond. Sulfonium alkynes can be easily synthesized and scaled up, and most of them are biocompatible. Candidate molecules were prepared and their potential use in various biological applications was tested.
Article
Chemistry, Multidisciplinary
Yun-Xuan Tan, Shijia Li, Lijuan Song, Xinhao Zhang, Yun-Dong Wu, Jianwei Sun
Summary: The first geminal hydroborative cyclization of enynes is disclosed in this study. Unlike known hydroborative cyclizations, this reaction adds hydrogen and boron to the same position, leading to a new reaction mode. By using a specific catalyst, a variety of gem-hydroborated bicyclic products with a cyclopropane unit can be rapidly formed from simple enyne substrates. Control experiments and calculations provide important insights into the reaction mechanism. Notably, two competing pathways may operate, depending on the substrate.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Chemistry, Organic
Guangyang Xu, Meirong Huang, Tao Zhang, Ying Shao, Shengbiao Tang, He Cao, Xinhao Zhang, Jiangtao Sun
Summary: In this study, an enantioselective insertion of a carbene into the Csp2-H bond of anisole derivatives was achieved using a chiral gold complex and a chiral phosphoric acid as the catalytic system, offering a novel approach for the synthesis of chiral α,α-diarylacetates.
Article
Chemistry, Multidisciplinary
Qiang Feng, Shijia Li, Zhiyang Li, Qiaolin Yan, Xiangfeng Lin, Lijuan Song, Xinhao Zhang, Yun-Dong Wu, Jianwei Sun
Summary: The study introduced a new reaction mode of ynones leading to the formation of novel products vinyl alpha-hydroxylboronates under mild ruthenium-catalyzed hydroboration conditions. It exhibited high efficiency, broad scope, and complete chemo-, regio-, and stereoselectivity, providing insights for developing new synthetic strategies.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2022)
Article
Chemistry, Multidisciplinary
Zhicheng Bao, Meirong Huang, Yan Xu, Xinhao Zhang, Yun-Dong Wu, Jianbo Wang
Summary: Bisborylalkanes are versatile bifunctional reagents in organic synthesis, with the ability to selectively convert their two boron moieties into other functional groups. This study presents a new strategy for synthesizing bisborylalkanes through the reaction of N-trisylhydrazones with diboronates, resulting in the transformation of bis(boryl) methane into 1,2-bis(boronates) through formal carbene insertion. This practical synthesis method allows for the broad substrate scope of 1,2-diboronates by readily deriving N-trisylhydrazones from corresponding aldehydes. Mechanistic studies uncover an unusual neighboring group effect of 1,1-bis(boronates) that explains the observed regioselectivity when unsymmetric 1,1-diboronates are utilized.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Multidisciplinary
Yong Wang, Yuxuan Li, Lei Wang, Shengtao Ding, Lijuan Song, Xinhao Zhang, Yun-Dong Wu, Jianwei Sun
Summary: In this study, a new method for efficient construction of gem-diboryl compounds with hetero-substituted carbon centers was developed. This method involves the alpha-dihydroboration of heteroalkynes and is a practical and atom-economic alternative to the conventional multistep synthetic strategy.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2023)
Article
Chemistry, Multidisciplinary
Ke Liao, Cho Ying Chan, Siqi Liu, Xinhao Zhang, Jiean Chen, Yong Huang
Summary: Functionalizing molecules through selective cleavage of carbon-carbon bonds is a promising approach, but the selective cleavage of inert C-sp3-C-sp3 bonds in hydrocarbon feedstocks remains challenging. This article presents a straightforward protocol for cleavage and functionalization of C(sp3)-C-sp3 bonds in alkylbenzenes using photoredox catalysis. Our method utilizes two distinct bond scission pathways depending on the nature of the benzylic substituents. This strategy provides a practical means of cleaving inert C-sp3-C-sp3 bonds in molecules without heteroatoms, generating various radical species.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2023)
Article
Chemistry, Physical
Linxing Zhang, Ping Chen, Xue-Peng Zhang, Chengxi Yang, Tian-Yu Sun, Xinhao Zhang, Yun-Dong Wu
Summary: The Catellani-type palladium/norbornene-cocatalyzed ortho-amination of aryl halides is widely used, but some key issues remain unresolved. Mass spectrometry and theoretical studies reveal the presence of a Cs-containing Pd-IV complex, the reactivity difference between 2-iodotoluene and morpholine-OBz, the coordination preference of Cs2CO3, the favored formation of Pd-IV intermediate with involvement of Cs2CO3, and the lower yield when using K2CO3 as a base.
Article
Engineering, Marine
Xinhao Zhang, Meng Zhou
Summary: This study proposes a method to build a general CNN model that can reconstruct images in unfamiliar areas. The model uses a more flexible U-net architecture to improve generality and was trained on images of different shapes to enhance performance. Results show that the model outperforms traditional interpolation methods when reconstructing for unfamiliar areas.
JOURNAL OF MARINE SCIENCE AND ENGINEERING
(2023)
Article
Chemistry, Multidisciplinary
Yimeng Du, Yuqing Zhang, Meirong Huang, Shushu Wang, Jianzheng Wang, Kongke Liao, Xiaojun Wu, Qiang Zhou, Xinhao Zhang, Yun-Dong Wu, Tao Peng
Summary: This study identified an efficient N-p-methoxybenzyl homoallylamine moiety for developing fluorescent probes for sensitive and selective detection of formaldehyde. The probes were successfully used to visualize endogenous formaldehyde in live mouse brain tissues and elevated levels in a mouse model of breast cancer, providing new chemical tools for studying formaldehyde in living systems.
Article
Chemistry, Organic
Haowen Ma, Jiajie Feng, Wei Zhou, Chen Chen, Zhuoji Deng, Fengtao Zhou, Yifan Ouyang, Xinhao Zhang, Qian Cai
Summary: Utilizing ureas as co-catalysts, a cooperative catalytic strategy has been developed for copper-catalyzed asymmetric intramolecular C-arylation reaction. By forming hydrogen bonds with 1,3-dicarbonyl structures, ureas activate the substrates, stabilize the intermediates and products, and improve reactivity and enantioselectivities.
ORGANIC & BIOMOLECULAR CHEMISTRY
(2021)