Article
Multidisciplinary Sciences
Yali Zhou, Xingjun Xu, Hongwei Sun, Guanyu Tao, Xiao-Yong Chang, Xiangyou Xing, Bo Chen, Chen Xu
Summary: This study reports effective platinum catalysts for hydroalkoxylation and hydroamination of unactivated alkenes, accommodating various alkene substitution patterns and providing a foundation for rational design of chiral catalysts through detailed mechanistic investigations.
NATURE COMMUNICATIONS
(2021)
Article
Chemistry, Multidisciplinary
Yang Yuan, Youcan Zhang, Wenbo Li, Yanying Zhao, Xiao-Feng Wu
Summary: A novel method for constructing amide bonds through anti-Markovnikov hydroaminocarbonylation of unactivated alkenes has been developed. Copper catalysis, hydroxylamine electrophile reagents, and poly(methylhydrosiloxane) (PMHS) were used under mild conditions. The reaction showed a high degree of tolerance towards various functional groups and efficiently converted unactivated terminal alkenes, 1,1-disubstituted alkenes, and cyclic alkenes to the corresponding amides with exclusive anti-Markovnikov selectivity.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Multidisciplinary
Yang Yuan, Youcan Zhang, Wenbo Li, Yanying Zhao, Xiao-Feng Wu
Summary: This paper reports a general method for the anti-Markovnikov hydroaminocarbonylation of unactivated alkenes under mild conditions, using copper catalysis in combination with hydroxylamine electrophile reagents and poly(methylhydrosiloxane) (PMHS) as a cheap and environmentally friendly hydride source. The reaction tolerates a variety of functional groups and efficiently converts unactivated terminal alkenes, 1,1-disubstituted alkenes, and cyclic alkenes to the corresponding amides with exclusive anti-Markovnikov selectivity (and high enantioselectivities/diastereoselectivities). Additionally, with minimal modification of the reaction conditions, alkynes can also undergo tandem hydrogenation-hydroaminocarbonylation to alkyl amides.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
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, 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, Physical
Satavisha Sarkar, Arghya Banerjee, Ming-Yu Ngai
Summary: In this study, a new metal-catalyzed reaction was developed to synthesize ketonylated carbocycles with important biological activities. The reaction offers simple operation, mild reaction conditions, and tolerance towards various functional groups.
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
Multidisciplinary Sciences
Geun Seok Lee, Daeun Kim, Soon Hyeok Hong
Summary: The use of alkyl chlorides in Pd-catalyzed Mizoroki-Heck coupling reactions remains a challenging issue due to the high thermodynamic barrier of alkyl chloride activation and the propensity of alkylpalladium complexes to undergo undesired beta-hydride elimination. However, this study demonstrates that alkyl chlorides, including tertiary ones, can efficiently participate in Mizoroki-Heck cross-coupling reactions under mild conditions via photoinduced Pd catalysis, offering great potential for late-stage functionalizations and molecular complexity.
NATURE COMMUNICATIONS
(2021)
Article
Chemistry, Organic
Jie Shi, Li-Yun Guo, Qu-Ping Hu, Yu-Tao Liu, Qing Li, Fei Pan
Summary: A photoredox-catalyzed radical cascade reaction has been developed for the synthesis of lactam-substituted gem-difluoroalkenes, providing a simple method with good functional group tolerance and high yields.
Article
Chemistry, Multidisciplinary
Mingda Li, Yangbin Jin, Yupeng Chen, Wanqing Wu, Huanfeng Jiang
Summary: This paper reports a new catalytic system for the efficient oxidative amination of unactivated olefins with primary aliphatic amines, leading to the formation of secondary allylic amines. The reaction proceeds through allylic C(sp3)-H activation and nucleophilic amination. The utility of this method is demonstrated in the late-stage modification and streamlined synthesis of drug molecules.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2023)
Article
Chemistry, Multidisciplinary
Zhan Dong, Qiongyao Tang, Changyu Xu, Li Chen, Haiting Ji, Sitian Zhou, Liangliang Song, Liang-An Chen
Summary: Transition-metal catalyzed intermolecular 1,2-diarylation of electronically unactivated alkenes is a widely studied topic, but most examples are limited to terminal alkenes. Furthermore, the asymmetric 1,2-diarylation of unactivated alkenes remains unsolved and is challenging. In this study, a highly efficient directed nickel-catalyzed reductive 1,2-diarylation of unactivated internal alkenes with high diastereoselectivities is described. Moreover, enantioselective 1,2-diarylation of unactivated terminal and challenging internal alkenes is achieved with good to high enantioselectivities and high diastereoselectivities by generating a cationic Ni-catalyst through the addition of alkali metal fluoride.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Physical
Fengqian Zhao, Jian-Xing Xu, Fu-Peng Wu, Xiao-Feng Wu
Summary: This communication describes a copper-catalyzed selectivity-reversed borocarbonylation. In the presence of CuOAc/BuPAd2 catalytic system, a series of unactivated terminal alkenes were transformed into β-boryl ketones in moderate yields, using sterically hindered alkyl bromides as the electrophiles.
JOURNAL OF CATALYSIS
(2023)
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, Multidisciplinary
Yunosuke Takekawa, Taiga Kodo, Kazunori Nagao, Hiroyuki Kakei, Kohei Takeuchi, Yusuke Sasak, Hirohisa Ohmiya
Summary: This manuscript presents an organophotoredox-catalyzed decarboxylative fluorination of alkyl redox active esters with triethylamine trihydrofluoride. The reaction proceeds via a radical-polar crossover mechanism to produce a carbocation equivalent under non-acidic and transition metal free conditions. This protocol enables the synthesis of various tertiary alkyl and benzyl fluorides in an environmentally friendly manner.
Article
Chemistry, Organic
Tomotoki Matsuo, Kazunori Nagao, Hirohisa Ohmiya
Summary: In this study, a visible light-mediated organophotoredox catalysis was developed for the cross-coupling between aliphatic carboxylic acid-derived redox active esters and organosilanes. This protocol enables the formation of C(sp3)-C(sp3), C(sp3)-C(sp2), and C(sp3)-C(sp) bonds under transition-metal free and mild reaction conditions. Additionally, the radical relay-type dicarbofunctionalization of styrene derivatives using organosilanes and aliphatic redox active esters was demonstrated.
TETRAHEDRON LETTERS
(2022)
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.
