Article
Chemistry, Applied
Lin Fan, Xinlong Yan, Changjiang Li, Yuxue Cao, Guodu Liu
Summary: In this study, a Cu-catalyzed intramolecular borylation-cross coupling reaction was developed, enabling the synthesis of both racemic and chiral borylated indolines. The reaction involved the simultaneous construction of C-C and C-B bonds using a Cu/phosphine ligand system. The method exhibited good to excellent yields and short reaction times. Asymmetric synthesis was also investigated, resulting in the successful synthesis of a chiral borylated indoline compound.
ADVANCED SYNTHESIS & CATALYSIS
(2023)
Article
Chemistry, Organic
Li-Ming Yin, Meng-Chan Sun, Xiao-Ju Si, Dandan Yang, Mao-Ping Song, Jun-Long Niu
Summary: An efficient Ni-catalyzed hydrodifluoroalkylation of unactivated alkenes with bromodifluoroacetate by using PhSiH3 as hydride source has been developed. The transformation provides aliphatic difluorides with anti-Markovnikov regioselectivity. A wide range of substrates, including highly remote alkenes, drug molecules, commercially available CF2 precursors, and even nonfluorinated substrates, are competent in this reaction under mild conditions, demonstrating the practicality of the strategy. Mechanistic studies suggest that the difluoroalkyl radical may be a key intermediate in this transformation.
Article
Chemistry, Physical
Dandan Yang, Hai Huang, He Zhang, Li-Ming Yin, Mao-Ping Song, Jun-Long Niu
Summary: The study achieved the Co-H-catalyzed intermolecular hydroamination of unactivated alkenes with various amine electrophiles by introducing a removable directing group. The catalytic system showed substrate-dependent regioselectivity, broad substrate scope, and simplified reaction conditions, providing a general and flexible protocol for the preparation of various amino acid derivatives.
Article
Chemistry, Multidisciplinary
Peng-Wei Sun, Ze Zhang, Xinyao Wang, Linshan Li, Yuxin Li, Zhengming Li
Summary: Metal-catalyzed hydroamination of alkenes is an effective method for synthesizing amines. This study developed a cobalt-catalyzed intermolecular hydroamination reaction using NFSI as the nitrogen source, which exhibited excellent selectivity and yield.
CHINESE JOURNAL OF CHEMISTRY
(2022)
Article
Chemistry, Physical
Peng-Fei Yang, Jian-Xing Liang, Han -Tong Zhao, Wei Shu
Summary: In this study, a straightforward method to access enantioenriched 1,n-diamines containing a chiral alpha-branched aliphatic amine is achieved through Ni-catalyzed asymmetric hydroamination. This method delivers good yields and excellent enantioselectivities with diverse substitution patterns, and exhibits excellent functional group tolerance.
Article
Chemistry, Organic
Yushan Cui, Yang Gao, Wanxuan Zhao, Yinglin Luo, Haiyi Xie, Yanping Huo, Xiao-Qiang Hu
Summary: This paper reports a new catalytic system that enables the regioselective hydroamination of unactivated alkenes, resulting in amino acid building blocks with excellent regiocontrol.
JOURNAL OF ORGANIC CHEMISTRY
(2022)
Article
Chemistry, Physical
Lang Cheng, Qi Tang, Ya-Mei Dai, Bi-Qin Wang, Ping Hu, Peng Cao, Feijie Song
Summary: The Rh-catalyzed intramolecular hydroarylation of olefin-tethered benzocyclobutenols via C-C bond activation has been achieved, providing an alternative approach to 3,3-disubstituted 2,3-dihydrobenzofurans bearing a 4-beta-keto moiety. The methodology features 100% atom economy and pH-and redox-neutral conditions, and is applicable to the late-stage functionalization of complex molecules. The asymmetric variant has also been achieved with excellent enantioselectivities.
Article
Chemistry, Multidisciplinary
Lu Wang, Minxu Shi, Xiaoping Chen, Nicholas Su, Weili Luo, Xiaheng Zhang
Summary: In this study, aromatic N-heterocyclic radicals were generated and utilized for the functionalization of unactivated alkenes, leading to the efficient synthesis of alkylated N-heterocyclic amines with medicinal relevance. This approach offers a novel retrosynthetic disconnection for the synthesis of therapeutic molecules and can be extended to the synthesis of densely functionalized heterocyclic amines.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Multidisciplinary
Efrey A. Noten, Rory C. McAtee, Corey R. J. Stephenson
Summary: This research discloses an intramolecular reaction that utilizes a nitrogen radical to form a C-N bond and repurposes the nitrogen atom's activating group to form a C-C bond, enabling the efficient synthesis of arylethylamines. The protocol utilizes photoredox catalysis under mild conditions.
Review
Chemistry, Multidisciplinary
Senjie Ma, John F. Hartwig
Summary: Catalytic intermolecular hydroamination of alkenes is a valuable method for the synthesis of amines with important applications in various fields. However, achieving high yield and selectivity is challenging due to the lack of thermodynamic driving force and the occurrence of side reactions. Late transition-metal complexes have shown advantages in catalyzing hydroaminations. This Account describes the progress in catalytic hydroamination reactions catalyzed by late transition-metal complexes, including additions to activated and unactivated alkenes, and the development of enantioselective hydroaminations.
ACCOUNTS OF CHEMICAL RESEARCH
(2023)
Article
Chemistry, Organic
Yang Gao, Yushan Cui, Yanping Huo, Jinhong Chen, Minwei She, Xianwei Li, Qian Chen, Xiao-Qiang Hu
Summary: A nickel-catalyzed polarity-reversed hydroamination of olefins has been developed, providing a convenient route to N-alkyl-2-aminobenzophenones intermediates. This method is compatible with a wide range of olefins and anthranils, delivering the desired amines in high yields, making it applicable for organic synthesis.
JOURNAL OF ORGANIC CHEMISTRY
(2021)
Article
Chemistry, Physical
Laura Talavera, Robert R. A. Freund, Huihui Zhang, Matthew Wakeling, Mara Jensen, Ruben Martin
Summary: In this study, a novel Ni-catalyzed 1,1-difunctionalization reaction of unactivated terminal alkenes is disclosed, allowing for the incorporation of two different heteroatom motifs across an olefin backbone. This method provides a streamlined approach to the synthesis of alpha-aminoboronic acid derivatives from simple precursors and exhibits simplicity and generality across a wide range of coupling counterparts.
Article
Chemistry, Physical
Laura Talavera, Robert R. A. Freund, Huihui Zhang, Matthew Wakeling, Mara Jensen, Ruben Martin
Summary: Here, a novel Ni-catalyzed 1,1-difunctionalization of unactivated terminal alkenes is disclosed, allowing for the incorporation of two different heteroatom motifs across an olefin backbone. This streamlines the access to alpha-aminoboronic acid derivatives from simple precursors, and the method exhibits simplicity and generality across a wide range of coupling counterparts.
Article
Chemistry, Multidisciplinary
Tao Zhong, Ji-Tao Yi, Zhi-Da Chen, Quan-Can Zhuang, Yong-Zhao Li, Gui Lu, Jiang Weng
Summary: This study successfully reported the first three-component aminofluorosulfonylation of unactivated olefins by merging photoredox-catalyzed proton-coupled electron transfer (PCET) activation with radical relay processes, efficiently affording various aliphatic sulfonyl fluorides featuring a privileged 5-membered heterocyclic core under mild conditions with good functional group tolerance. The synthetic potential of the sulfonyl fluoride products was examined by diverse transformations including SuFEx reactions and transition metal-catalyzed cross-coupling reactions, with mechanistic studies demonstrating the involvement of amidyl radicals, alkyl radicals, and sulfonyl radicals in this difunctionalization transformation.
Article
Chemistry, Multidisciplinary
Benxiang Zhang, Jiayan He, Yi Li, Tao Song, Yewen Fang, Chaozhong Li
Summary: Acylphosphonates with the 5,5-dimethyl-1,3,2-dioxophosphinanyl skeleton have been developed as efficient intermolecular radical acylation reagents for cobalt-catalyzed Markovnikov hydroacylation of unactivated alkenes at room temperature. The protocol shows broad substrate scope and good functional group compatibility, providing satisfactory yields of branched ketones. The proposed mechanism involves Co-H mediated hydrogen atom transfer and subsequent trapping of alkyl radicals by acylphosphonates.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2021)
Article
Chemistry, Organic
Yusuke Miyamoto, Yuto Sumida, Hirohisa Ohmiya
Summary: A new type of alkylborate has been developed for radical generation through direct photoexcitation, utilizing organoboronic acids or potassium trifluoroborates as reactants. The easy availability of organoboron compounds is a key advantage, and the excited states of these borates can also function as strong reductants for various transformations.
Article
Chemistry, Organic
Rino Kobayashi, Shotaro Shibutani, Kazunori Nagao, Zenichi Ikeda, Junsi Wang, Ignacio Ibanez, Matthew Reynolds, Yusuke Sasaki, Hirohisa Ohmiya
Summary: An organophotoredox-catalyzed decarboxylative cross-coupling between azole nucleophiles and aliphatic carboxylic acid-derived redox-active esters is demonstrated. This reaction efficiently installs various alkyl fragments onto the nitrogen atom of azole nucleophiles under mild and transition-metal-free conditions. The use of a pyridinium additive successfully inhibits the formation of elimination byproducts from the carbocation intermediate, making this reaction applicable to the synthesis of molecule with potential protein-degrading properties.
Article
Multidisciplinary Sciences
Yuki Matsuki, Nagisa Ohnishi, Yuki Kakeno, Shunsuke Takemoto, Takuya Ishii, Kazunori Nagao, Hirohisa Ohmiya
Summary: This article discusses the successful application of NHC-catalyzed aryl radical reactions in various arylations. The method allows for the generation of aryl radicals from halides through single electron transfer processes, providing a metal-free approach for radical reactions.
NATURE COMMUNICATIONS
(2021)
Article
Chemistry, Multidisciplinary
Masakiyo Mukai, Kazunori Nagao, Shigeru Yamaguchi, Hirohisa Ohmiya
Summary: A molecular field-based regression analysis was used to design chiral ligands with improved enantioselectivity in NHC-Cu-catalyzed asymmetric carbonyl additions.
BULLETIN OF THE CHEMICAL SOCIETY OF JAPAN
(2022)
Article
Chemistry, Organic
Koh Watanabe, Mitsutaka Takeda, Kazunori Nagao, Hirohisa Ohmiya
Summary: This article describes a catalytic reductive cross-coupling reaction between arylaldehydes and aryl electrophiles using a silylboronate as a terminal reductant. The protocol provides a new opportunity to access 1,1-diarylmethanol derivatives without the need for rare metals or highly basic organometallic reagents.
EUROPEAN JOURNAL OF ORGANIC CHEMISTRY
(2022)
Article
Chemistry, Organic
Marin Kemmochi, Yusuke Miyamoto, Yuto Sumida, Hirohisa Ohmiya
Summary: The photoexcitable borate enables Minisci C-H alkylation of heteroarenes, providing a clean system using alkylborate, O-2, and visible light. Direct photoexcitation of alkylborate generates tertiary, secondary, and primary-alkyl radicals, including methyl radicals, offering a choice for the functionalization of heteroarenes.
ASIAN JOURNAL OF ORGANIC CHEMISTRY
(2022)
Article
Chemistry, Multidisciplinary
Masanari Nakagawa, Yuki Matsuki, Kazunori Nagao, Hirohisa Ohmiya
Summary: We have demonstrated the Markovnikov hydroalkoxylation of unactivated alkenes using alcohols through a triple catalysis involving photoredox, cobalt, and Brönsted acid catalysts. This triple catalysis allows the realization of three key elementary steps in a single catalytic cycle: Co(III) hydride generation, metal hydride hydrogen atom transfer (MHAT), and oxidation of the alkyl Co(III) complex. The precise control of protons and electrons by the three catalysts eliminates the need for strong acids and external reductants/oxidants in the conventional methods.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2022)
Article
Multidisciplinary Sciences
Taiga Kodo, Kazunori Nagao, Hirohisa Ohmiya
Summary: This paper reports a new method of semipinacol rearrangement using photochemical approach, enabling the synthesis of compounds with sp(3)-rich scaffolds.
NATURE COMMUNICATIONS
(2022)
Article
Chemistry, Physical
Naho Takemura, Yuto Sumida, Hirohisa Ohmiya
Summary: This article presents a visible-light-driven method for silyl radical generation, which is further enhanced by recent advancements in silylboronate synthesis.
Article
Chemistry, Multidisciplinary
Yunosuke Takekawa, Masanari Nakagawa, Kazunori Nagao, Hirohisa Ohmiya
Summary: In this study, a quadruple catalysis system involving N-heterocyclic carbene, cobalt, photoredox, and Bronsted base is demonstrated to achieve branch-selective hydroacylation of styrenes with aromatic and aliphatic aldehydes. This protocol provides a convenient and atom-economical method for the synthesis of branched ketones from readily available materials by transferring a formyl hydrogen of aldehydes as a hydrogen radical equivalent onto the terminal carbon of an alkene through controlled electron and proton transfers.
CHEMISTRY-A EUROPEAN JOURNAL
(2023)
Article
Chemistry, Multidisciplinary
Rikako Nakamura, Takeru Yamazaki, Yui Kondo, Miho Tsukada, Yusuke Miyamoto, Nozomi Arakawa, Yuto Sumida, Taketoshi Kiya, Satoshi Arai, Hirohisa Ohmiya
Summary: Researchers have developed a new method for caging/uncaging bioactive molecules using a photo-cleavable carbon-boron bond. This method allows for the caging of previously uncageable molecules, such as acetylcholine, providing a unique tool for optopharmacology to study neuronal mechanisms.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2023)
Article
Multidisciplinary Sciences
Kenji Ota, Kazunori Nagao, Dai Hata, Haruki Sugiyama, Yasutomo Segawa, Ryosuke Tokunoh, Tomohiro Seki, Naoya Miyamoto, Yusuke Sasaki, Hirohisa Ohmiya
Summary: This study demonstrates a light-driven radical-polar crossover mechanism for the tertiary alkylation of phosphorus atoms in nucleotides, enabling the synthesis of alkylphosphonate structures that are difficult to obtain using existing methods.
NATURE COMMUNICATIONS
(2023)
Article
Chemistry, Multidisciplinary
Ryoto Oya, Kenji Ota, Masaaki Fuki, Yasuhiro Kobori, Masahiro Higashi, Kazunori Nagao, Hirohisa Ohmiya
Summary: The biomimetic design based on the iron(iv)-oxo porphyrin & pi;-cation radical species in cytochrome P450 enzymes has been extensively studied. In this study, the functions of this species were translated to an & alpha;-ketoacyl phosphonium species comprised of non-metal atoms and used as a light-activated oxygenation auxiliary for ortho-selective oxygenation of anilines. The process exhibited high regioselectivity and chemoselectivity.
Article
Chemistry, Multidisciplinary
Ryoto Oya, Kenji Ota, Masaaki Fuki, Yasuhiro Kobori, Masahiro Higashi, Kazunori Nagao, Hirohisa Ohmiya
Summary: The biomimetic design of a transition metal complex based on the iron(iv)-oxo porphyrin & pi;-cation radical species has been translated to an & alpha;-ketoacyl phosphonium species for ortho-selective oxygenation of anilines. Visible light irradiation activates the excited state of the auxiliary, which acts as a transient oxidant, providing high regioselectivity and chemoselectivity.
Review
Chemistry, Multidisciplinary
Yuto Sumida, Hirohisa Ohmiya
Summary: Visible-light-mediated chemical processes have been extensively studied, leading to cutting-edge synthetic chemistry by controlling radical generation and excited-state transformations. While photoredox chemistry is important, it often involves photocatalysts and redox processes, complicating reactions. A breakthrough in this field is the development of a system free of photocatalysts, providing more straightforward and energetically efficient methods.
CHEMICAL SOCIETY REVIEWS
(2021)
