Article
Chemistry, Multidisciplinary
Morgane de Robichon, Thilo Kratz, Frederike Beyer, Julian Zuber, Christian Merten, Thorsten Bach
Summary: Substituted bicyclo[1.1.0]butanes add enantioselectively to 2(1H)-quinolones upon irradiation, leading to the formation of products with a chiral bicyclo[2.1.1]hexane skeleton. A two-point hydrogen bond between the quinolone and the template is responsible for stereocontrol in the photocycloaddition reaction. The chiral template can be recovered and reused, and sensitization is a suitable tool for performing the reaction with visible light.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2023)
Article
Chemistry, Physical
Tomohiro Kikuchi, Takeshi Yasui, Yoshihiko Yamamoto
Summary: Transition-metal mediated carbon-carbon single-bond cleavage of cyclopropenes has been achieved via an intramolecular cycloaddition with alkynes, leading to the formation of 1,2-fused cyclopentadienes. Fused cycloheptatrienes were also synthesized through the cycloaddition of cyclopropene-diynes.
Article
Chemistry, Multidisciplinary
Marcel Haerterich, Benedikt Ritschel, Merle Arrowsmith, Julian Boehnke, Ivo Krummenacher, Ashwini K. Phukan, Holger Braunschweig
Summary: This study reports the first examples of thermally induced, transition-metal-free cross-metathesis between an organic alkyne and inorganic B=B double bonds, resulting in the formation of novel compounds with unique properties. These compounds form via a biradical mechanism and possess distinctive reducibility.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2021)
Article
Chemistry, Multidisciplinary
Yanyao Liu, M. Kevin Brown
Summary: A strategy utilizing temporary ring constraint to achieve photosensitized [2 + 2] cycloadditions is reported. This strategy overcomes challenges with the cycloaddition of acyclic substrates and has been demonstrated in the synthesis of valuable heterocycles and biatriosporin D.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2023)
Article
Chemistry, Organic
Yating Dai, Hongchun Huang, Shuangshuang Liang, Yanli Yin, Xu Ban, Xiaowei Zhao, Zhiyong Jiang
Summary: In this study, an enantioselective intermolecular [3 + 2] cycloaddition of N-arylcyclopropylamines with 2-aryl acrylates/ketones and cyclic ketone-derived terminal olefins via asymmetric photoredox catalysis was reported. A dual catalyst system involving DPZ and a chiral phosphoric acid was effective for the transformations, leading to a wide array of valuable cyclopentylamines with high yields, ee's, and drs. Elaborate modulation of the ester group of 2-aryl acrylates was shown to be effective in improving reactivity, thereby enabling the success of the transformations.
Article
Chemistry, Physical
Takeshi Yasui, Rine Tatsumi, Yoshihiko Yamamoto
Summary: In this study, a dual cobalt and photoredox catalysis was utilized for the [2+2+2] cycloaddition of enediynes to produce tricyclic cyclohexadienes with a quaternary bridgehead carbon. The use of a chiral ligand, (S)-Segphos, enabled highly enantioselective reactions, leading to highly enantio-enriched cyclohexadienes.
Article
Chemistry, Multidisciplinary
Chu-Hong Ou, Ying-Ming Pan, Hai-Tao Tang
Summary: In this study, we designed and synthesized a porous organic polymer with NHC as the core structure, which exhibited higher catalytic activity and recyclability compared to homogeneous NHC. The polymer successfully catalyzed the cycloaddition reaction of aldehyde and ethyl isocyanoacetate under electro-oxidation conditions. This study provides a reference for the development of new green catalytic systems.
SCIENCE CHINA-CHEMISTRY
(2022)
Article
Polymer Science
Santhosh Kumar Podiyanachari, Maciej Barlog, Marc Comi, Salahuddin Attar, Saeed Al-Meer, Mohammed Al-Hashimi, Hassan S. Bazzi
Summary: Polymerization of ROMP-derived polyM1 and polyM2 shows differences in the content of trans olefins and the optical properties in solution and film state. Both polymers exhibit excellent characteristics as electron-accepting materials with good film-forming ability and thermal stability, despite some differences in film morphology observed by AFM analysis.
JOURNAL OF POLYMER SCIENCE
(2021)
Review
Chemistry, Organic
Jiali Huang, Lei Zhang, Xiangtai Meng
Summary: Nitrogen- and sulfur-containing heterocyclic compounds are widely found in bioactive natural products and drug molecules. Efforts have been made to develop convenient and efficient strategies for synthesizing these compounds. Pyridinium zwitterions with unique reactivity have played a significant role in the construction of heterocycles. In recent years, these zwitterions have been extensively used in cyclization reactions to synthesize novel heterocyclic compounds.
ORGANIC CHEMISTRY FRONTIERS
(2023)
Article
Chemistry, Multidisciplinary
Sebastian A. Schwengers, Chandra Kanta De, Oleg Grossmann, Joyce A. A. Grimm, Natascha R. Sadlowski, Gabriela G. Gerosa, Benjamin List
Summary: A single-flask synthesis method for efficient Bronsted acids was developed, allowing for the rapid production of imidodiphosphate-based compounds. The catalysts exhibit high structural confinement and a wide acidity range, with one catalyst showing highly enantioselective sulfoxidation activity. Additionally, a novel super acidic catalyst motif, IDPii, was discovered, demonstrating extreme reactivity in the alpha-methylation reaction of a silyl ketene acetal with methanol.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2021)
Article
Chemistry, Multidisciplinary
Yao Xu, Hai-Xiang Gao, Chengkai Pan, Yue Shi, Chi Zhang, Genping Huang, Chao Feng
Summary: By using photoredox catalysis, we have achieved the (3+3) dipolar cycloaddition of nitrones with aryl cyclopropanes. This reaction exhibits excellent regio- and stereoselectivity and can be applied to a variety of aryl cyclopropane substrates.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Multidisciplinary
Yulin Han, Anni Qin, Qian Zhang, Xue Zhang, Hui Qian, Shengming Ma
Summary: The Rh-catalyzed reaction allows for the efficient synthesis of cis-fused bicyclic products with excellent selectivity and tolerance towards synthetically useful functional groups. The proposed mechanism involves the rapid racemization of the allene moiety in the starting materials.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Chemistry, Multidisciplinary
Mingkai Zhang, Peilin Xu, Alex J. Vendola, Christophe Allais, Anne-Marie Dechert Schmitt, Robert A. Singer, James P. Morken
Summary: This paper describes an easily synthesized chiral diazaborolidine that is inexpensive, stable, and exhibits excellent stereoselection across multiple reaction classes. These versatile compounds have utility in four different classes of cycloaddition reactions, offering good yield and stereoselectivity. X-ray structure analysis provides insight into the origin of stereocontrol.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Chemistry, Applied
Augustin Nouaille, Xavier Pannecoucke, Thomas Poisson, Samuel Couve-Bonnaire
Summary: This study presents an efficient ruthenium-catalyzed CM reaction method, successfully allowing various alkenes to react with methyl 2-fluoroacrylate to obtain trisubstituted fluoroalkenes for the first time. Additionally, an unprecedented TON value for the CM reaction involving fluoroalkenes was achieved, demonstrating good tolerance and effectiveness with a wide range of olefin partners.
ADVANCED SYNTHESIS & CATALYSIS
(2021)
Article
Chemistry, Multidisciplinary
Jianfeng Jiang, Xia Wang, Shengping Liu, Sichen Zhang, Binmiao Yang, Yu Zhao, Shenci Lu
Summary: We report an unprecedented gold and oxidative NHC relay catalysis for highly enantioselective cascade annulation between readily available alpha-amino-ynones with enals. This method utilizes in situ-generated pyrrolin-4-ones as a novel and versatile synthon, reacting with alpha,beta-unsaturated acylazolium intermediates generated from enals by oxidative NHC catalysis to produce pyrrole-fused lactones in high yield and excellent enantioselectivity. The utility of the lactone products is demonstrated by their facile conversion to densely functionalized pyrroles and pyrrolin-4-ones with high yields and excellent stereopurity.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
