Review
Chemistry, Applied
Anna Gulevskaya, Daria Tonkoglazova
Summary: Helicenes are polycyclic aromatic molecules with unique structures and properties. They have been widely applied in material science, nanoscience, and other fields. However, synthesizing helicenes remains a challenge, and alkyne cyclizations show great potential as a method. This review focuses on the development and applications of alkyne-based syntheses of carbo- and heterohelicenes.
ADVANCED SYNTHESIS & CATALYSIS
(2022)
Article
Multidisciplinary Sciences
Aijie Cai, Wenhao Yan, Xiaojun Zeng, Samson B. Zacate, Tzu-Hsuan Chao, Jeanette A. Krause, Mu-Jeng Cheng, Wei Liu
Summary: The authors present a copper-catalyzed radical relay approach for the carbo-difluoromethylation of alkenes, which introduces CF2H groups and complex alkyl or aryl groups into alkenes with broad substrate scope and functional group compatibility. Mechanistic studies suggest a unique ligand effect on the reactivity of the Cu-CF2H species.
NATURE COMMUNICATIONS
(2021)
Review
Chemistry, Physical
Tong-De Tan, Ze-Shu Wang, Peng-Cheng Qian, Long-Wu Ye
Summary: Ynamides, as electron-rich heteroatom-substituted alkynes, have proven to be versatile reagents for organic synthesis and have received extensive attention. Radical reactions of ynamides, categorized by radical attack at the alpha-position and beta-position, are reviewed in this article to highlight reaction selectivity, scope, mechanism, and applicability. The aim is to provide a comprehensive summarization of these advances to guide the further development of ynamide chemistry.
Article
Chemistry, Multidisciplinary
Yang-Bo Chen, Li-Gao Liu, Can-Ming Chen, Yi-Xi Liu, Bo Zhou, Xin Lu, Zhou Xu, Long-Wu Ye
Summary: In this study, a copper-catalyzed atroposelective diyne cyclization was disclosed for the synthesis of a range of axially chiral arylpyrrole biaryls with good to excellent yields and enantioselectivities. This method represents the first synthesis of mono-substituted 3-arylpyrrole atropisomers and the first example of atroposelective diyne cyclization and atropisomer construction using vinyl cations.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Multidisciplinary
Maximilian Scheruebl, Constantin G. Daniliuc, Armido Studer
Summary: The article introduces the application of arynes as radical acceptors, showing how the stable radical TEMPO can react with different ortho-substituted benzynes to generate aryl radicals for subsequent cyclizations, eventually being trapped by TEMPO. This method provides a novel approach for the convenient synthesis of various dihydrobenzofurans, oxindoles, and sultones.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2021)
Article
Chemistry, Applied
Thibaut Duhail, Samir Messaoudi, Guillaume Dagousset, Jerome Marrot, Christiane Andre-Barres, Emmanuel Magnier, Elsa Anselmi
Summary: We prepared S-perfluoroalkyl benzodithiazole trioxides as radical perfluoroalkylating reagents. The synthesis of these compounds was achieved on a multi-gram scale through oxidative cyclization. The structures and properties of the molecules were investigated using X-Ray diffraction, DFT calculations, and cyclic voltammetry. The enhanced reactivity of the cyclic sulfoximines compared to their open analogues was confirmed by photoredox catalysis experiments.
ADVANCED SYNTHESIS & CATALYSIS
(2023)
Article
Chemistry, Multidisciplinary
Wongyu Lee, Dongwook Kim, Sangwon Seo, Sukbok Chang
Summary: In this study, a polar-radical relay strategy is reported for the alpha-C-H amination of cyclic amines using N-chloro-N-sodio-carbamates. The strategy involves the in situ generation of a cyclic iminium intermediate using N-iodosuccinimide (NIS) as an oxidant, followed by a series of polar and radical reactions to achieve controlled C-N bond formation. The method provides a facile and regioselective access to a broad range of alpha-amino cyclic amines and demonstrates excellent applicability for functionalization of biologically relevant compounds.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Chemistry, Organic
Zheng Sun, Yu Shao, Shuwei Zhang, Yuxian Zhang, Yu Yuan, Xiaodong Jia
Summary: Oxidative desymmetrization of isoindolines was achieved through TBN initiated radical sp(3) C-H activation relay (CHAR), providing a series of omega-hydroxylactams in high yields. The reaction shows broad substrate scope and good functional group tolerance, with key steps involving C-H bond oxidation, dioxygen trapping, and intramolecular 1,5-H shift.
SYNTHESIS-STUTTGART
(2021)
Article
Chemistry, Organic
Fei Liu, Jiapian Huang, Xinyu Wu, Feihua Du, Linghui Zeng, Jie Wu, Zhiyuan Chen
Summary: A simple and low-cost tandem sulfonylation/cyclization of 1,5-diene, aryldiazonium salt, and DABCOmiddot(SO2)2has been developed. This base-promoted multicomponent reaction provides a green and economic synthesis of sulfonylated pyrrolidones under transition-metal-free and moisture/oxygen-insensitive reaction conditions, delivering a wide range of products in moderate to high yields with excellent functional group compatibility.
JOURNAL OF ORGANIC CHEMISTRY
(2022)
Article
Chemistry, Multidisciplinary
Bastian Muriel, Jerome Waser
Summary: A radical-mediated amination of cyclopropenes is reported, leading to tetrasubstituted alkenyl nitrile derivatives and allowing for the one-pot synthesis of highly functionalized polycyclic aromatic compounds. This transformation enables the synthesis of nitrile-substituted alkenes and aromatic compounds from readily available cyclopropenes.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2021)
Article
Chemistry, Physical
Qing-Peng Liu, Xiaoyu Chen, Ning Yu, Yu-Lin Li, Kui-Cheng He, Wei-Hao Zheng, Yu-Qiang Zhou, Kun Jiang, Limin Yang, Ye Wei
Summary: In this work, a relay C-H functionalization protocol using iron catalysis was described, which enables the synthesis of various pyridines and pyridones. The reaction involves the functionalization of three C-H bonds and the generation of three chemical bonds and two rings in one step. The reaction mechanism was investigated through control experiments and kinetic isotope effect experiments.
Article
Chemistry, Organic
Lanjun Su, Huan Sun, Jikai Liu, Chengming Wang
Summary: A quaternary carbon center with an oxindole motif was constructed via NHC-catalyzed transition-metal and aldehyde-free intermolecular Heck-type alkyl radical addition. The redox-neutral protocol offers a simple procedure, broad substrate scope, good functional group tolerance, and scalability to gram scale, with a mechanism involving two sets of SET processes and an NHC radical cation intermediate.
Article
Chemistry, Multidisciplinary
Biping Xu, Weiping Su
Summary: In this paper, we report a transition metal-free, operationally simple, general method for the straightforward synthesis of 2-substituted benzoxazoles from readily available cyclohexanones and aliphatic primary amines. The key to the success of this method is the use of TEMPO as a mild oxidant, which selectively oxidizes the reaction intermediates through its multiple reactivity modes, allowing the individual steps to proceed in succession. This protocol demonstrates high reliability and excellent functional-group tolerance, enabling the synthesis of structurally diverse products, including marketed drugs, drug candidates, and natural products that are unattainable by existing methods.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Engineering, Environmental
Lihua Yang, Weiqi Su, Yingyao He, Binhua Yan, Lijuan Luo, Tiangang Luan
Summary: This study aims to investigate the transformation of E2 in water containing fresh or aged DOM surrogates. The results showed that aged DOM produced higher concentrations of hydroxyl radicals, which contributed to the removal of E2. Additionally, the removal of E2 was enhanced by increasing DOM concentration, dissolved oxygen, and light supply. These findings have important implications for understanding the biogeochemical cycle and risk assessment of E2 in natural aquatic environments.
Review
Chemistry, Organic
Alexander S. Budnikov, Igor B. Krylov, Andrey Lastovko, Bing Yu, Alexander O. Terent'ev
Summary: O-substituted derivatives of N-hydroxyphthalimide (NHPI) have gained attention as convenient reagents for generating free radicals under mild conditions. N-alkoxyphtalimides are effective in generating alkoxy free radicals, leading to selective synthetic transformations. This review discusses visible light induced reactions, including hydrogen atom transfer and beta-scission, as well as non-photochemical tin-mediated processes.
ASIAN JOURNAL OF ORGANIC CHEMISTRY
(2022)
