Article
Chemistry, Multidisciplinary
Rahul K. Shukla, Akshay M. Nair, Chandra M. R. Volla
Summary: Recent years have witnessed the development of transition metal catalyzed C-H activation as a powerful method in organic synthesis. Allene reactivity has attracted considerable interest among synthetic chemists. Although directing group assisted C(sp(2))-H functionalization with allenes has been well studied, coupling with more challenging aliphatic C(sp(3))-H bonds remains a challenge. Here, we report a Pd(ii) catalyzed aliphatic C(sp(3))-H dienylation using allenyl acetates directed by 8-aminoquinoline. A wide range of carboxylic acids, including fatty acids and amino acids, were effectively functionalized at the beta and gamma positions to provide diversely functionalized 1,3-dienes. Preliminary mechanistic studies suggest that the success of this transformation relies on the crucial role of the base. The reaction proceeds through regioselective 2,3-migratory insertion of the allene with the alkylpalladium(ii) species followed by beta-acetoxy elimination.
Article
Chemistry, Organic
Lei Liang, Ge Guo, Chen Li, Song-Lin Wang, Yue-Hui Wang, Hai-Ming Guo, Hong-Ying Niu
Summary: The study demonstrates Cu-catalyzed intermolecular alkynylation and allylation of unactivated C(sp(3))-H bonds with SOMO-philes via HAT, using N-fluoro-sulfonamide as a reagent, resulting in high yields, good regioselectivity, and functional-group compatibility. Late-stage functionalization of natural products and drug molecules is also shown in the research.
Review
Chemistry, Multidisciplinary
Erika L. Lucas, Nelson Y. S. Lam, Zhe Zhuang, Hau Sun Sam Chan, Daniel A. Strassfeld, Jin-Quan Yu
Summary: CONSPECTUS: The development of asymmetric beta-C-H activation reactions for organic synthesis has been described in this Account. By studying reaction mechanisms and stereochemical properties, both strongly coordinating and weakly coordinating directing groups were designed to achieve beta-C-H activation of aliphatic acids and carboxylic acids, respectively. The development of five classes of chiral ligands enabled enantioselective beta-C-H activation reactions of readily available substrates.
ACCOUNTS OF CHEMICAL RESEARCH
(2022)
Review
Chemistry, Multidisciplinary
Bijin Li, Mazen Elsaid, Haibo Ge
Summary: C(sp(3))-H functionalization is an important method to increase molecular complexity. Despite the initial challenges of inertness and high bond-dissociation energies, these hurdles can be overcome through selective strategies, leading to efficient construction of C-C and C-X bonds. This review discusses transition-metal-catalyzed site-selective gamma- and delta-C(sp(3))-H functionalization reactions and explores their applications in late-stage functionalization of medicinal compounds and construction of complex molecules of medicinal importance.
Article
Chemistry, Multidisciplinary
Rupeng Qi, Chao Wang, Yumei Huo, Hongli Chai, Hongying Wang, Zijian Ma, Liangyu Liu, Rui Wang, Zhaoqing Xu
Summary: Asymmetric functionalization of C-H is a attractive strategy in asymmetric synthesis, and photoredox catalysis has emerged as an efficient way to synthesize organic compounds under mild conditions.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2021)
Article
Chemistry, Organic
Zi-Yu Dong, Jia-Hui Zhao, Peng Wang, Jin-Quan Yu
Summary: In this study, a class of bifunctional monoprotected amino-imidazoline (MPAI) ligands were developed and applied in Pd-catalyzed C(sp(3))-H arylation of free aliphatic acids. The newly developed MPAI ligand enables the use of 1.0 equiv of aliphatic acids containing an alpha hydrogen for the first time.
Article
Chemistry, Multidisciplinary
Jia-Lin Tu, Ao-Men Hu, Lin Guo, Wujiong Xia
Summary: In this study, undirected iron-catalyzed C(sp3)-H borylation, thiolation, and sulfinylation reactions were developed using the photoinduced ligand-to-metal charge transfer (LMCT) process. These reactions showed broad substrate scope and unconventional regioselectivity.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2023)
Article
Chemistry, Multidisciplinary
Liang Hu, Guangrong Meng, Jin-Quan Yu
Summary: This study reports the first Pd(II)-catalyzed intermolecular fi-methylene C(sp3)-H arylation of free aliphatic acids using bidentate pyridine-pyridone ligands. The bite angle of the ligand plays a key role in promoting fi-methylene C-H activation of free carboxylic acid. This transformation provides a disconnection for alkylation of arenes with simple aliphatic acids.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2022)
Article
Chemistry, Multidisciplinary
Yin-Xia Wang, Feng-Ping Zhang, Hao Chen, Yue Li, Jiang-Fei Li, Mengchun Ye
Summary: Enantioselective Ni-catalyzed C(sp(3))-H bond activation was achieved using a phosphine oxide-ligated Ni-Al bimetallic catalyst, leading to the synthesis of a series of chiral N-containing heterocycles in good yields and high enantioselectivity.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Chemistry, Organic
Qiu-Cui Zheng, Si-Yuan Peng, Si-Qi Cong, Xin-Yu Ning, Yan Guo, Meng-Jiao Li, Wen-Shu Wang, Xiao-Jie Cui, Fei-Xian Luo
Summary: In this study, an unexpected dehydrogenation reaction was successfully explored through C(sp3)-H arylation and C-N coupling, leading to the synthesis of bioactive compounds with good regioselectivity and functional group compatibility. This research provides an alternative pathway to achieve molecular complexity and diversity through multiple C-H bond activations.
Article
Chemistry, Organic
Jinquan Zhang, Shuaizhong Zhang, Hongbin Zou
Summary: The study introduces a new Pd-catalyzed gamma-C(sp(3))-H selective alkylation and alkenylation reaction with removable 7-azaindole as a directing group. Acid and base were found to be decisive regulators for selective alkylation and alkenylation on the same substrate under the same reaction conditions. The results demonstrate the potential of the strategy for structurally diverse aliphatic chain extension and functionalization.
Article
Chemistry, Organic
Michael Hitt, Andrei N. Vedernikov
Summary: N-Trifluoroacetoxyquinuclidinium trifluoroacetate was prepared in situ and used as a reagent for the high-yielding oxidative trifluoroacetoxylation of benzylic C-H bonds. The reaction showed selectivity for 2 degrees benzylic C-H bonds and suggested a hydrogen-atom transfer mechanism for alkylbenzenes.
Article
Chemistry, Organic
Ya-Nan Ding, Ning Li, Yan-Chong Huang, Yang An, Yong-Min Liang
Summary: In this study, a practical and highly efficient method for visible-light-induced copper-catalyzed N-aminoquinoline-directed asymmetric C(sp(3))-C(sp(3))-H glycosylation was reported. Additionally, C-glycopeptides were synthesized through the glycosylation of nondeoxysugars with amino acids. This research provides a new approach for the synthesis of C-glycopeptides and C-glycoamino acids.
Review
Chemistry, Multidisciplinary
Bin Liu, Andrew M. Romine, Camille Z. Rubel, Keary M. Engle, Bing-Feng Shi
Summary: Transition-metal-catalyzed, coordination-assisted C(sp(3))-H functionalization has revolutionized synthetic planning by providing increased access to strategic positions in organic molecules. Challenges like high temperatures, difficulty in removing directing groups, and limited metal options beyond palladium still remain. This review aims to cover literature since 2004, highlighting current state-of-the-art methods, limitations, and discussing synthetic applications and reaction mechanisms.
Article
Multidisciplinary Sciences
Rong-Hua Wang, Wei-Wei Xu, Hongli Wu, Yue Li, Jiang-Fei Li, Tao Zhang, Genping Huang, Mengchun Ye
Summary: In this study, we report a new phosphine oxide-ligated Ni-Al bimetallic catalyst that can efficiently activate secondary benzylic C-H bonds via 4-membered nickelacycles, leading to the synthesis of high-yield α,β-unsaturated γ-lactams.
NATURE COMMUNICATIONS
(2022)
Article
Chemistry, Multidisciplinary
Xuemei Liu, Chaonan Cui, Shuoshuo Wei, Jinyu Han, Xinli Zhu, Qingfeng Ge, Hua Wang
Summary: This study presents a new strategy for designing efficient photocatalysts that can convert CO2 into hydrocarbons by utilizing synergistic catalytic sites. The findings provide a solution for the selective photocatalytic reduction of CO2 to CH4.
Article
Chemistry, Multidisciplinary
Chengxian Hu, Dan Wang, Lu Wang, Ying Fu, Zhengyin Du
Summary: A novel one-pot, three-component reaction conducted under electrochemical conditions was studied. The reaction involved 2-aminothiophenols, aldehydes, and malononitrile, using TBABF4 as an electrolyte and CuI as a catalyst. The proposed reaction mechanism suggested that CuI served as an electron relay. This method offers simplified operation, high atom economy, and mild reaction conditions.
Article
Chemistry, Multidisciplinary
Zhi Yang, Yu Chen, Linxi Wan, Yuxiao Li, Dan Chen, Jianlin Tao, Pei Tang, Fen-Er Chen
Summary: A highly enantioselective method for the complete hydrogenation of pyrimidinium salts using Ir/(S,S)-f-Binaphane complex as the catalyst was developed. This method provides easy access to fully saturated chiral hexahydropyrimidines, which are prevalent in many bioactive molecules. The reactions exhibit high yields and enantioselectivities under mild reaction conditions without additives. Successful application of this methodology in a continuous flow fashion further extends its practical utility.
Article
Chemistry, Multidisciplinary
Tina Jeoh, Jennifer Danger Nill, Wujun Zhao, Sankar Raju Narayanasamy, Liang Chen, Hoi-Ying N. Holman
Summary: In this study, the enzymatic hydrolysis of cellulose was investigated using real-time infrared spectromicroscopy. The spatial heterogeneity of cellulose was found to impact the hydrolysis kinetics. Hydration affected cellulose ordering, and Cel7A preferentially removed less extensively hydrogen bonded cellulose.
Article
Chemistry, Multidisciplinary
Tiphaine Richard, Walid Abdallah, Xavier Trivelli, Mathieu Sauthier, Clement Dumont
Summary: An effective method of grafting functionalities onto lignin based on glycerol carbonate has been developed using an efficient nickel-catalysed telomerisation reaction. This method allows lignin to have new reactive functions and reduces the glass transition temperatures of modified lignins, thereby expanding the application range of lignin-based resins.
Article
Chemistry, Multidisciplinary
Jing Qi, Xiyan Wang, Gan Wang, Srinivas Reddy Dubbaka, Patrick ONeill, Hwee Ting Ang, Jie Wu
Summary: This study presents a green and environmentally friendly approach for the synthesis of imides using electrocatalytic oxidation with H2O as the oxygen source. The method eliminates the need for toxic or expensive oxidants and achieves high yields under mild reaction conditions. It shows broad substrate compatibility and potential for industrial applications.
Article
Chemistry, Multidisciplinary
Babasaheb Sopan Gore, Lin-Wei Pan, Jun-Hao Lin, Yi-Chi Luo, Jeh-Jeng Wang
Summary: Here, we report a visible light-promoted intramolecular radical cascade reaction for the construction of fluorenol and naphthalene-fused cyclopropyl carbaldehyde derivatives. This method offers mild reaction conditions, a broad substrate scope, excellent step efficiency, and scalability, without the need for external chemical oxidants. The novelty of this protocol was demonstrated by synthesizing chrysene analogs and performing late-stage functionalizations.
Article
Chemistry, Multidisciplinary
Juho Antti Sirvio, Idamaria Romakkaniemi, Juha Ahola, Svitlana Filonenko, Juha P. Heiskanen, Ari Ammala
Summary: This article discusses the method of using supramolecular interaction between an aromatic hydrogen bond donor and lignin to achieve rapid delignification of softwood at low temperatures.
Article
Chemistry, Multidisciplinary
Yunyan Meng, Chunxiang Pan, Na Liu, Hongjiang Li, Zixiu Liu, Yao Deng, Zixiang Wei, Jianbin Xu, Baomin Fan
Summary: A novel visible light-driven synthesis method for 2,3-diamines has been developed, which has mild conditions, avoids the use of metal reagents, and can synthesize diamines and diols in one pot.
Article
Chemistry, Multidisciplinary
Mingqing Huang, Haiyang Huang, Mengyao You, Xinxin Zhang, Longgen Sun, Chao Chen, Zhichao Mei, Ruchun Yang, Qiang Xiao
Summary: A direct air-oxidized strategy for the synthesis of benzo[b]phosphole oxides was developed in this study. Arylphosphine oxides were transformed into phosphinoyl radicals, which were further combined with various alkynes to achieve the desired products. DFT calculations revealed the mechanism of phosphinoyl radical formation.
Article
Chemistry, Multidisciplinary
Anwei Wang, Jiayin Huang, Chunsheng Zhao, Yu Fan, Junfeng Qian, Qun Chen, Mingyang He, Weiyou Zhou
Summary: This study demonstrates an innovative strategy for the aerobic oxidation of C(sp(3))-H bonds using gamma-valerolactone. By optimizing the reaction conditions and utilizing specific catalysts, efficient oxidation of C(sp(3))-H bonds is achieved with good chemoselectivity in certain cases.
Article
Chemistry, Multidisciplinary
Shun Li, Likai Tong, Zhijian Peng, Bo Zhang, Xiuli Fu
Summary: Sulfide compounds show promise as electrocatalysts for water splitting, but their performance is limited by factors such as limited active sites and hindered substance transport. This study successfully prepared a high-entropy sulfide (ZnCoMnFeAlMg)(9)S-8, which reduced grain size and increased specific surface area, enabling the realization of a dual-functional catalyst with multiple catalytic sites. High entropy also modulated the electronic properties of sulfides, reducing the potential energy barrier for hydrolysis. This research introduces a new approach for functionalizing high entropy nanomaterials and improves the performance of water splitting catalysts.