Article
Chemistry, Organic
Jia Zhou, Zi-Hao Li, Le Wang, Jun-Chen Kang, Xun-Hui Wang, Shu-Yu Zhang
Summary: This study introduces a highly efficient enantioselective para-C-H alkylation of aniline derivatives promoted by a base/Co/indeno-pybox ligand system, leading to the construction of enantioenriched compounds with all-carbon quaternary stereocenters. In addition, biologically or medicinally active indoles can be synthesized through Co-catalyzed asymmetry synthesis method. The role of the (acac)(-) anion of Co(acac)(2) in chiral control during the nucleophilic reaction is highlighted by density functional theory calculations and experimental results.
Article
Chemistry, Organic
Qin Wang, Yan Shi, Xiaoli Huang, Yongzhuang Wang, Jiao Jiao, Yuhai Tang, Jing Li, Silong Xu, Yang Li
Summary: A highly efficient Ru(II)-catalyzed regio- and stereospecific hydro-oxycarbonylation reaction has been developed for unsymmetrical internal alkynes bearing a difunctional 2-pyridyloxy directing group with carboxylic acids. This reaction provides allylic (Z)-enol esters in good to excellent yields with a broad substrate scope under mild conditions. The difunctional directing group can be diversely derivatized, particularly allowing for allylic substitution with various nucleophiles to afford beta-functionalized (Z)-enol esters without directing groups.
Article
Chemistry, Organic
Sandip Kumar Gupta, Niranjan Panda
Summary: A Pd(II)-catalyzed dehydrogenative remote C4-H coupling of indoles with unfunctionalized arenes at room temperature was achieved using a weak chelating trifluoroacetyl group as a directing group. Various substituents on the arenes were compatible with the dehydrogenative cross coupling reaction.
JOURNAL OF ORGANIC CHEMISTRY
(2023)
Article
Chemistry, Organic
Bhawani, Vikki N. Shinde, Sonam, Krishnan Rangan, Anil Kumar
Summary: A successful description of a mechanochemical, solvent-free Ru(II)-catalyzed reaction for the alkenylation of N-heteroaryl arenes with alkynes has been achieved, resulting in moderate to good yields with good functional group compatibility and broad substrate scope.
JOURNAL OF ORGANIC CHEMISTRY
(2022)
Review
Chemistry, Multidisciplinary
Chao Pei, Claire Empel, Rene M. Koenigs
Summary: C-H functionalization is a rapidly advancing field in organic synthesis and is crucial for minimizing the ecological and economic impact. However, the ubiquity and low reactivity of C-H bonds present challenges, often requiring harsh conditions. Recent research has revealed a new approach, using a single transition-metal complex as both a photosensitizer and catalyst, to achieve C-H functionalization without an exogenous photosensitizer.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Chemistry, Multidisciplinary
Bingnan Du, Yuxin Ouyang, Qishu Chen, Wing-Yiu Yu
Summary: A NiH-catalyzed thioether-directed cyclometalation strategy allows for remote methylene C-H bond amidation of unactivated alkenes. This strategy shows high yields and remarkable regioselectivity in the preparation of amide products.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2021)
Article
Multidisciplinary Sciences
Leipeng Xie, Shenghao Wang, Lanlan Zhang, Lei Zhao, Chun Luo, Linping Mu, Xiuguang Wang, Chao Wang
Summary: The authors presented a method to add aryl and amino groups to alkenes regio- and diastereoselectively via nickel catalysis and a removable directing group. This method enables high levels of regio-, chemo- and diastereocontrol, and is compatible with broad substrate scope and high functional group tolerance. The utility of this method in site-selective modification of pharmaceutical agents has been demonstrated.
NATURE COMMUNICATIONS
(2021)
Review
Chemistry, Multidisciplinary
Wei Zhao, Hou-Xiang Lu, Wen-Wen Zhang, Bi-Jie Li
Summary: Alkenes are versatile compounds that can be obtained from industry or synthesized organically. The development of catalytic asymmetric alkene hydrofunctionalizations is driven by the widespread occurrence of alkenes, allowing for the construction of complex chiral molecules. By using a coordinating group on the alkene substrate, reactivity can be enhanced and the control of regio-, diastereo-, and enantioselectivities can be facilitated. Through this strategy, several alkene hydrofunctionalization methods with excellent controls have been developed.
ACCOUNTS OF CHEMICAL RESEARCH
(2023)
Article
Chemistry, Organic
Yogesh N. Aher, Amit B. Pawar
Summary: An external oxidant free Ru(II)-catalyzed C-H functionalization/annulation of primary benzylamines with sulfoxonium ylides has been developed for the synthesis of isoquinolines. The reaction utilizes free amine as a directing group, which is generally considered to be a poor directing group. This work presents the first example of Ru-catalyzed C-H functionalization of benzylamines under redox-neutral conditions. The detection of the amine-directed ruthenacyclic intermediate using high-resolution mass spectrometry corroborated the involvement of free amine as a directing group.
JOURNAL OF ORGANIC CHEMISTRY
(2022)
Article
Chemistry, Organic
Liqun Yang, Wenkui Lu, Xiaoyu Wu, Yan Lu, Xiaomin Xie, Zhaoguo Zhang
Summary: In this study, a Rh2(OAc)(4)/XantPhos catalyzed hydrosilylation reaction of alkynes with tertiary silanes in acetonitrile was reported, which showed regio- and stereoselectivity and could be used for the synthesis of beta-(Z) vinylsilanes. This method exhibited excellent compatibility with various functional groups.
ORGANIC CHEMISTRY FRONTIERS
(2023)
Article
Chemistry, Organic
Yi-Xin Xu, Yu-Qing Liang, Zhong-Jian Cai, Shun-Jun Ji
Summary: A novel chelation-assisted C-H arylation reaction of benzo[h]quinoline is described in this study. The reaction, using [RuCl2(p-cymene)]2 as the catalyst and cheap and easily accessible arylsulfonyl chlorides as the arylation source, exhibits simple reaction conditions, a broad substrate scope, and good functional group tolerance. The successful application of bioactive-molecule-based sulfonyl chlorides further emphasizes the potential utility and importance of this desulfitative C-H arylation protocol.
Article
Chemistry, Organic
Yoichi Kitazawa, Takuya Kochi, Fumitoshi Kakiuchi
Summary: In this study, an ortho-C-H alkenylation of aromatic ketones with unsymmetric internal alkynes was achieved using an iron phosphine complex, Fe(PMe3)4, as the catalyst. The addition of a catalytic amount of PtBu3 improved the yield of the products. The alkenylation reaction exhibited regio- and stereoselectivity, leading to the formation of corresponding styrene derivatives.
JOURNAL OF ORGANIC CHEMISTRY
(2023)
Article
Chemistry, Organic
Somratan Sau, Arghadip Ghosh, Majji Shankar, Manash Protim Gogoi, Akhila Kumar Sahoo
Summary: The study demonstrates a unprecedented thioamide-directed cobalt-catalyzed umpolung annulation reaction for the synthesis of highly substituted 2-amidoindenones. The transformation shows regioselectivity and constructs diverse structures, showcasing broad scope and success on a gram scale.
Article
Chemistry, Multidisciplinary
Nikolaos Kaplaneris, Marcelo Vilches-Herrera, Jun Wu, Lutz Ackermann
Summary: Catalyzed C-H activation is an important tool for molecular assembly, enabling efficient assembly of complex structures. Ruthenium catalysis offers cost-effective and mild C-H functionalization with unique reactivity, contributing to sustainability in industrial settings. Sustainable ruthenium-catalyzed C-H activation can be achieved using water as a reaction medium.
ACS SUSTAINABLE CHEMISTRY & ENGINEERING
(2022)
Article
Chemistry, Organic
Yoichi Kitazawa, Takuya Kochi, Fumitoshi Kakiuchi
Summary: We present a study on the ortho-C-H alkenylation of aromatic ketones with unsymmetric internal alkynes catalyzed by an iron phosphine complex, Fe(PMe3)4. The addition of a catalytic amount of PtBu3 as an additive was shown to enhance the product yields. This alkenylation reaction displays regio- and stereoselectivity, yielding the corresponding styrene derivatives.
JOURNAL OF ORGANIC CHEMISTRY
(2023)
Review
Chemistry, Multidisciplinary
Koji Hirano, Masahiro Miura
Summary: This Perspective describes recent advances in highly selective amination reactions using electrophilic amination reagents. By utilizing the concept of nitrogen umpolung, challenging aminofunctionalizations of alkenes and alkynes have been achieved, leading to densely functionalized complex and often chiral alkylamines with high selectivity.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2022)
Review
Chemistry, Multidisciplinary
Koji Hirano
Summary: The development of new C-N bond forming strategies is crucial due to the importance of nitrogen atom in bioactive molecules and functional materials. This account presents the nitrogen-umpolung-enabled copper-catalyzed highly selective amination protocols developed by the author's research group. The application of these methods to the synthesis of alkyl-amines with rich functionality is demonstrated.
BULLETIN OF THE CHEMICAL SOCIETY OF JAPAN
(2023)
Article
Chemistry, Multidisciplinary
Rikuto Tanaka, Shiho Ochiai, Asumi Sakai, Yoshinosuke Usuki, Bubwoong Kang, Tetsuro Shinada, Tetsuya Satoh
Summary: The C-H alkenylation of N-acetylcarbazoles using a cationic Cp*Rh(III) catalyst at the C1-position results in the formation of 1-alkenylcarbazoles. Further alkenylation is achieved with the use of a cationic (CpRh)-Rh-E(III) catalyst, leading to the formation of 1,8-dialkenylcarbazoles. The direct alkenylation procedure, combined with easy removal of the acetyl directing group, provides a straightforward synthetic route to 1- and/or 8-alkenyl-N-H-carbazole derivatives. One of the 1-alkenyl-N-H-carbazoles obtained in this study exhibits solvatochromism.
CHEMISTRY-AN ASIAN JOURNAL
(2023)
Article
Chemistry, Organic
Shogo Nakamura, Soshi Nishino, Koji Hirano
Summary: A copper-catalyzed regioselective hydroamination method was developed to synthesize alpha-aminophosphonates from alpha,beta-unsaturated phosphonates, which are of interest in medicinal chemistry. The use of an umpolung, electrophilic amination strategy with a hydroxylamine derivative is key to achieving the desired regioselectivity, as compared to the conventional nucleophilic hydroamination conditions with the parent amine. The article also discusses the asymmetric synthesis using a chiral bisphosphine ligand and its application in a related silylamination reaction.
JOURNAL OF ORGANIC CHEMISTRY
(2023)
Article
Chemistry, Inorganic & Nuclear
Yuji Nishii, Masahiro Miura
Summary: Sulfur-containing functional groups have recently gained attention as useful directing groups for the direct catalytic C-H transformation of aromatic and heteroaromatic compounds. In this study, we summarize our recent work on site-selective substitution using thioether directing groups under either Cp*Rh(III) or Cp*Ir(III) catalysis. The thioether groups can be easily removed and transformed to other functional groups. These reactions appear to be important in pharmaceutical and materials chemistry.
PHOSPHORUS SULFUR AND SILICON AND THE RELATED ELEMENTS
(2023)
Article
Chemistry, Organic
Soshi Nishino, Koji Hirano
Summary: A copper-catalyzed regio- and diastereoselective borylacylation reaction has been developed to synthesize β'-boryl-β-ketoesters with high anti-diastereoselectivity. The reaction can also be extended to borylcarbamoylation, and enantioselective variants have been achieved using chiral phosphoramidite-ligated copper complexes.
ASIAN JOURNAL OF ORGANIC CHEMISTRY
(2023)
Review
Chemistry, Physical
Yuji Nishii, Masahiro Miura
Summary: Dibenzo-fused five-membered heteroaromatic compounds, such as dibenzofuran, carbazole, and dibenzothiophene, are important structural units in various polycyclic heteroaromatic compounds. The intramolecular C-H/C-H biaryl coupling of diaryl (thio)ethers and amines based on palladium(II) catalysis under oxidative conditions is an effective method for their construction. This mini-review briefly summarizes representative examples of constructing structurally intriguing pi-extended polycyclic heteroaromatics through catalytic coupling reactions.
Article
Chemistry, Organic
Kazutoshi Nishimura, Shibo Xu, Yuji Nishii, Koji Hirano
Summary: A metal-free, phosphenium-dication-mediated sequential C-P and C-C bond forming reaction has been developed for the concise synthesis of (di)benzophosphole derivatives from readily available and simple arylalkynes and phosphinic acids. The application of this protocol to multiple cyclization reactions and fully intermolecular three-component coupling-type reactions is also described.
Article
Chemistry, Organic
Ayumi Inami, Yuji Nishii, Koji Hirano, Masahiro Miura
Summary: In this study, a new synthetic method was developed using vinyl selenone as a surrogate for phenylacetylene in the Rh-catalyzed annulative coupling reaction. This method successfully produced 3,4-nonsubstituted isoquinoline compounds. The reaction conditions were mild and the vinyl selenone could be recovered and recycled.
Article
Chemistry, Organic
Soshi Nishino, Yuji Nishii, Koji Hirano
Summary: A copper-catalyzed stereoselective 1,4-acylboration reaction between B(2)pin(2) and pivalic anhydride with a,b-unsaturated esters has been developed, yielding (E)-allylboronates with two distinct oxygenated functional groups at the gamma positions, a challenging transformation to achieve using other methods. The chemoselective post functionalizations of Bpin and pivalate moieties in the product are also demonstrated.
Article
Chemistry, Organic
Ayako Nishida, Yasuhito Inai, Yoshinosuke Usuki, Tetsuya Satoh
Summary: The dehydrogenative cyclization of 9-anthracenecarboxylic acids and 2-substituted 1-naphthoic acids catalyzed by rhodium(III) leads to the formation of fused lactones through peri C-H bond cleavages. These aromatic carboxylic acids also undergo dehydrogenative coupling with styrenes and successive Wacker-type cyclization under palladium catalysis to construct 3-benzylidenebenzo[de]isochromen-1-one frameworks.
ASIAN JOURNAL OF ORGANIC CHEMISTRY
(2023)
Article
Chemistry, Multidisciplinary
Atsushi Matsumura, Yoshinosuke Usuki, Tetsuya Satoh
Summary: The sp(3) C-H acetoxylation at the beta-position of alpha,alpha-disubstituted alpha-amino acids can be smoothly achieved under palladium catalysis using PhI(OAc)(2) as the reagent. This reaction provides an easy synthetic route to non-natural beta-acetoxy-alpha-amino acids. The reaction of alpha-aminocyclopropanecarboxylic acid selectively generates an acyclic gamma-acetoxy-alpha,beta-unsaturated amino acid through ring-opening.
CHEMISTRY-SWITZERLAND
(2023)
Article
Chemistry, Multidisciplinary
Shotaro Nakamura, Kohei Okubo, Yuji Nishii, Koji Hirano, Norimitsu Tohnai, Masahiro Miura
Summary: This study synthesized bent-type bisbenzofuropyrazine derivatives with good solubilities and investigated their physical and optical properties. The materials exhibited different luminescence properties depending on their crystal packing structures and concentration-dependent vapochromic luminescence. These findings have potential implications for sensing systems.
CHEMISTRY-A EUROPEAN JOURNAL
(2023)
Article
Chemistry, Organic
Yoshinosuke Usuki, Yuka Tanaka, Miyu Morii, Tetsuya Satoh
Summary: Antimycins are well-known antifungal metabolites produced by Streptomyces bacteria. Neoantimycin and its analogues, featuring a 15-membered tetraester ring, have shown effectiveness as regulators of the oncogenic proteins GRP78/BiP and K-Ras. Isoneoantimycin, isolated as a minor metabolite during neoantimycin fermentation, is the first reported antibiotic in the antimycin family without the macrolide core. This study focuses on the total synthesis and stereochemical assignment of isoneoantimycin for structure-activity studies on neoantimycins, successfully achieving synthesis of the target molecule with the same stereochemistry as natural isoneoantimycin.
ORGANIC & BIOMOLECULAR CHEMISTRY
(2023)
