Article
Chemistry, Organic
Aleksey Zerov, Irina A. Boyarskaya, Olesya Khoroshilova, Irina N. Lavrentieva, Alexander Slita, Ekaterina O. Sinegubova, Vladimir V. Zarubaev, Aleksander V. Vasilyev
Summary: Trimethylsilyl ethers of 1,5-diaryl-3-(trifluoromethyl)pent-1-en-4-yn-3-oles in the superacid TfOH give rise to reactive conjugated CF3-allylic-propargylic cations, which, in the presence of arenes and excess TfOH, lead to the formation of E-1,1,5-triaryl-3-(trifluoromethyl)-pent-2-en-4-ynes and CF3-bicyclic dihydroanthracene derivatives, respectively. These two main reaction pathways are dependent on the nucleophilicity of aryl substituents in CF3-pentenynes and external aromatic molecules.
JOURNAL OF ORGANIC CHEMISTRY
(2021)
Article
Chemistry, Physical
Ameya S. Burde, Sherry R. Chemler
Summary: Saturated heterocycles containing oxygen and sulfur are present in biologically significant molecules. This article presents a complementary approach using copper catalysis to synthesize enantioenriched compounds with high selectivity from acyclic alkenols.
Article
Chemistry, Inorganic & Nuclear
Jiandong Guo, Dongju Zhang, Xiaotai Wang
Summary: This study presents a novel hydrodefluorination reaction initiated by nickel hydride HAT, providing mechanistic insights and implications for developing new metal hydride HAT-initiated reactions.
DALTON TRANSACTIONS
(2021)
Article
Chemistry, Applied
Lei Liu, Wangqin Zhang, Chao Xu, Jiaying He, Zhenhui Xu, Zehui Yang, Fei Ling, Weihui Zhong
Summary: An atom and step economy cascade trifluoromethylation/cyclization of unactivated alkene with Langlois reagent as a CF3 source is successfully demonstrated. The synthesis of a variety of polycyclic quinazolinones was achieved in 52-81% yields without the requirement of transition metal catalysts or oxidants. The use of Langlois reagent in this strategy provides the advantages of bench-stability, cost-effectiveness, and high efficiency. The gram-scale reaction, broad substrate scope, and good functional group tolerance further confirm the synthetic usefulness of this protocol.
ADVANCED SYNTHESIS & CATALYSIS
(2022)
Article
Chemistry, Organic
Yang Ming, Huang Danfeng, Wang Kehu, Han Tongyu, Zhao Pengfei, Wang Feng, Wang Junjiao, Su Yingpeng, Hu Yulai
Summary: The silver salt-catalyzed [3+2] cycloaddition reaction of trifluoromethylated N-acylhydrazones and ethyl isocyanoacetate was investigated, which efficiently produced a series of trifluoromethylated 2-imidazoline compounds in high yields with excellent stereoselectivity, providing a novel and efficient method for their synthesis.
CHINESE JOURNAL OF ORGANIC CHEMISTRY
(2022)
Article
Chemistry, Organic
Timothy A. A. Davidson, Samiha Anam, Heyao Shi, Darren J. J. Dixon
Summary: This article describes the cobalt-catalyzed reaction between 1,3-dithiolanes and Grignard reagents for the efficient synthesis of multi-substituted alkene products. The method is applicable to various benzylic dithiolane substrates, providing good to excellent yields of di-, tri-, and tetra-substituted 1,1-diaryl alkene products. By using benzylic Grignard reagents and aryl aldehyde-derived 1,3-dithiolanes, natural product-derived stilbene architectures with exquisite E selectivity can be accessed. The simplicity, low catalyst loadings, and scalability of the method demonstrate its general utility.
ASIAN JOURNAL OF ORGANIC CHEMISTRY
(2023)
Article
Chemistry, Applied
Satenik Mkrtchyan, Michal Jakubczyk, Suneel Lanka, Muhammad Yar, Khurshid Ayub, Mohanad Shkoor, Michael Pittelkow, Viktor O. Iaroshenko
Summary: In this study, two mild, solvent-free mechanochemical coupling transformations of CF3 group with nitro compounds were successfully demonstrated, leading to amides or Schiff bases. Ytterbia was used as a catalyst to facilitate the process, which involves C-F bond activation and the use of Si-based reductants/oxygen scavengers. This work represents the first example of utilizing mechanical energy to promote the transformation of the inert CF3 group into other functionalities.
ADVANCED SYNTHESIS & CATALYSIS
(2021)
Article
Chemistry, Organic
Yubo Duan, Shu-Ning Lu, Zuguang Yang, Zhengkai Chen, Xiao-Feng Wu
Summary: An efficient and straightforward strategy for the divergent synthesis of trifluoromethyl-substituted (dihydro)pyrimidoindolones via Rh(iii)-catalyzed C-H activation/annulation of N-carbamoylindoles with CF3-imidoyl sulfoxonium ylides has been achieved. The cascade reaction proceeds through a C-H imidoylmethylation, tautomerization and intramolecular nucleophilic addition sequence, leading to the construction of a wide range of functionalized pyrimidoindolone derivatives in good to excellent yields under redox-neutral conditions.
ORGANIC CHEMISTRY FRONTIERS
(2023)
Article
Chemistry, Organic
Si Wen, Yuqing Zhang, Qingyu Tian, Yanhui Chen, Guolin Cheng
Summary: The ruthenium(ii)-catalyzed C-H activation/annulation reaction of benzoic acids and CF3-imidoyl sulfoxonium ylides, enabled by weak O-coordination, has been achieved to synthesize a series of 3-trifluoromethylisoquinolinones in yields ranging from 37% to 75%.
ORGANIC CHEMISTRY FRONTIERS
(2022)
Article
Chemistry, Multidisciplinary
Dong Wei, Han-Yu Lu, Han-Zhe Miao, Chen-Guo Feng, Guo-Qiang Lin, Yingbin Liu
Summary: An efficient and environmentally friendly method for preparing substituted indene derivatives using water as the sole solvent has been developed. This reaction can be conducted under air, tolerates a wide range of functional groups, and can be easily scaled up. Bioactive natural products like indriline can be synthesized using this protocol. Preliminary results show the possibility of achieving enantioselectivity.
Article
Chemistry, Organic
Xu Zhao, Chenrui Fan, Jianbo He, Yunfei Luo
Summary: Alkynyl chlorides were discovered to be novel electrophiles, capable of forming a single regioisomer of [3+2] annulation adducts with cyclic ketimines through rhodium catalysis. The alkenyl chloride moiety in the products offered a valuable functional handle for diverse transformations. Therefore, this research not only provided a synthetic protocol for obtaining unsymmetrically substituted indenyl amines but also presented a highly divergent solution for decorating the substituting group through postmanipulation of the chloride.
Article
Chemistry, Multidisciplinary
Hafiza Tayyaba Shahzadi, Saman Fatima, Naseem Akhter, Meshari Alazmi, Alshammari Nawaf, Kamaleldin B. Said, Amer AlGhadhban, Abdel Moneim E. Sulieman, Rahman Shah Zaib Saleem, Ghayoor Abbas Chotana
Summary: This paper describes an iridium-catalyzed C-H borylation method for CF3-substituted pyridines, enabling the installation of boronic ester groups with steric control. The method is solvent-free and compatible with various functional groups. Although the borylated pyridines can be isolated in good yields, the alpha-borylated pyridines have a short shelf life. The boronic ester derivatives of CF3-substituted pyridines can serve as useful precursors in synthesis.
Article
Chemistry, Multidisciplinary
Katsumasa Tanaka, Hiroshi Hattori, Ryota Yabe, Takahiro Nishimura
Summary: In this study, an iridium-catalyzed sp(3) C-H alkylation reaction was conducted to achieve high yields in the reaction between N-methyl groups and 1,5- and 1,6-dienes, resulting in the formation of five- and six-membered carbocyclic compounds. The use of a chiral bidentate phosphine ligand allowed for the asymmetric synthesis of cyclic compounds.
CHEMICAL COMMUNICATIONS
(2022)
Article
Chemistry, Multidisciplinary
Tongyu Bi, Yi Xu, Xin Xu, Bixi Tang, Qing Yang, Yi Zang, Zhenyang Lin, Jia Li, Weibo Yang
Summary: A Rh(III)-catalyzed C-H alkylation macrocyclization was developed to access CF3-substituted macrolides with novel bioactivities. The chemoselectivity between C-H alkylation and olefination macrocyclization was controllable, and the CF3-substituted macrolides exhibited potent anti-inflammation activities against TNF-alpha, IL-6 and CCL2 mRNA expression.
CHINESE CHEMICAL LETTERS
(2022)
Article
Chemistry, Physical
Xavier Abel-Snape, Gina Wycich, Mark Lautens
Summary: A palladium-catalyzed three-component domino reaction for accessing indene derivatives is described. The reaction involves the sequential formation of three bonds, with the first two resulting from inter- and intramolecular carbopalladation, and the final bond arising from an attack by a terminating nucleophilic reagent. The starting tether on the iodoarene can be modified to yield either indenes or benzofulvenes. Additionally, the use of an oxabicycle as an acetylene surrogate is demonstrated, and the enantioselective synthesis of indenes is preliminarily explored.
Review
Chemistry, Multidisciplinary
Keiji Mori
Summary: An efficient catalytic internal redox reaction, which does not require transition metals commonly used in conventional CH bond functionalization, has been developed to construct complex polycycles that are challenging to synthesize by traditional methods.
BULLETIN OF THE CHEMICAL SOCIETY OF JAPAN
(2022)
Article
Chemistry, Organic
Tatsuhiro Uchikura, Sosuke Yokohama, Mona Murakami, Takahiko Akiyama
SYNTHESIS-STUTTGART
(2022)
Article
Chemistry, Physical
Tatsuhiro Uchikura, Nanami Kamiyama, Toshiki Mouri, Takahiko Akiyama
Summary: A visible-light-driven enantioselective radical addition to imines was developed by directly exciting a chiral phosphoric acid-imine complex. Chiral amine products were obtained with high enantioselectivities using benzothiazolines as the radical precursors (up to 98% ee). Mechanistic studies revealed the photoredox activities of the chiral phosphoric acid-imine complex in oxidizing benzothiazolines.
Article
Chemistry, Organic
Tatsuhiro Uchikura, Kureha Aruga, Riku Suzuki, Takahiko Akiyama
Summary: In this study, an enantioselective Friedel-Crafts alkylation reaction was developed using chiral phosphoric acid as the catalyst to react N-unprotected alkynyl trifluoromethyl ketimines with pyrroles, resulting in the synthesis of chiral primary alpha-trifluoromethyl-alpha-(2-pyrrolyl)propargyl-amines with high enantioselectivity. The alkynyl group of the adducts can be transformed without a loss of optical purity, leading to optically active alpha-trifluoromethylated amines bearing various substituents.
Article
Chemistry, Organic
Tatsuhiro Uchikura, Kazushi Tsubono, Yurina Hara, Takahiko Akiyama
Summary: This study reports a dual-role EDA-SET/HAT photoreaction system for carbon-carbon bond formation using a phenol catalyst and aryl iodide. Irradiation of the EDA complex with visible light generates an aryl radical, which abstracts a hydrogen atom from an sp3 carbon to form an alkyl radical.
JOURNAL OF ORGANIC CHEMISTRY
(2022)
Article
Chemistry, Organic
Keiji Mori, Hiroto Okawa
Summary: Hydride shift mediated C(sp(3))-H bond functionalization is a useful synthetic tool for constructing fused cycles. Most studies have focused on reactions with aniline and phenol derivatives, while reactions using substrates with a carbon linker between the aromatic ring and the heteroatom have been overlooked. Recently, various novel reactions starting from these substrates have been developed.
TETRAHEDRON LETTERS
(2022)
Article
Chemistry, Applied
Issei Nakamura, Masahiro Anada, Shunsuke Sueki, Kosho Makino, Keiji Mori
Summary: We have developed a sequential hydride shift process involving a [1,8]-hydride shift, leading to the synthesis of nine-membered carbocycle-fused piperidine derivatives in good yields. The use of 30 mol% Yb(OTf)(3) and 10 mol% iPr(2)NEt as catalysts is crucial for the success of this reaction.
ADVANCED SYNTHESIS & CATALYSIS
(2023)
Article
Chemistry, Multidisciplinary
Tatsuhiro Uchikura, Haruka Nakamura, Hinata Sakai, Takahiko Akiyama
Summary: An efficient and widely applicable silyl radical addition reaction was developed using 2-silylated dihydroquinazolinone derivatives under photocatalytic conditions. Electron-deficient alkenes and styrene derivatives underwent hydrosilylation to give addition products in good to high yields. Mechanistic studies revealed that the photocatalyst functioned as an energy transfer catalyst rather than a photoredox catalyst.
CHEMISTRY-A EUROPEAN JOURNAL
(2023)
Article
Chemistry, Organic
Tatsuhiro Uchikura, Irene Sanchez-Sordo, Tatsuhiko Yoshimura, Yudai Makino, Hiroto Osakabe, Takahiko Akiyama
Summary: We have developed a chiral phosphoric acid-catalyzed enantioselective Friedel-Crafts alkylation reaction between pyrroles and indolylmethanols. Wide substrate scope was observed, and a chiral all-carbon quaternary center was constructed at the 3 position of indoles in high yields with high to excellent enantioselectivities (up to 99% ee).
JOURNAL OF ORGANIC CHEMISTRY
(2023)
Article
Chemistry, Organic
Ken Yamanomoto, Tadachika Matsudaira, Takahiko Akiyama
Summary: We have developed a straightforward method for the synthesis of a-hydroxyamino ketones by utilizing the benzoylation reaction under organophotocatalysis. The reaction proceeds through a benzoyl radical addition to nitrone, and benzothiazoline is found to be a more suitable radical precursor than Hantzsch ester.
Article
Chemistry, Multidisciplinary
Tatsuhiro Uchikura, Sotaro Kato, Yudai Makino, Megumi J. J. Fujikawa, Masahiro Yamanaka, Takahiko Akiyama
Summary: Desymmetrization is a crucial technique for synthesizing chiral compounds, especially chiral biaryls. This study presents an enantioselective synthesis of axially chiral biaryls through desymmetrization using chiral palladium phosphate as the catalyst for C(sp(3))-H activation. Mechanistic investigations reveal that C-H activation plays a crucial role in determining the rate and enantiomeric selectivity. To the best of our knowledge, this is the first report on the asymmetric desymmetrization of axially chiral compounds via C(sp(3))-H activation.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2023)
Article
Chemistry, Organic
Hiromasa Ogawa, Hiroto Okawa, Keiji Mori
Summary: We investigated the effects of substituents on the aromatic rings in a diarylmethylamine unit, which we named the 'butterfly'-type amine unit, in an aminothiourea catalyst. The catalyst with a 3,5-bis(trifluoromethyl)phenyl group showed the best results, achieving excellent chemical yield and enantioselectivity in an asymmetric Michael reaction. Importantly, this catalyst demonstrated superior catalytic ability as a chiral catalyst compared to the well-known Takemoto catalyst, and this characteristic was observed in various asymmetric reactions.
Article
Chemistry, Multidisciplinary
Suzuka Shibata, Koutarou Amano, Tatsuhiro Kojima, Keiji Mori
Summary: A Lewis acid-catalyzed 1,3-aminomethyl migration reaction was studied. Treatment of δ-amino acid derivatives with a catalytic amount of Sc(OTf)(3) resulted in smooth migration of the aminomethyl group, leading to the formation of & beta;-amino acid derivatives in moderate to good yields. Detailed investigation revealed that the migration reaction proceeded via a fragmentation/recombination pathway.
CHEMICAL COMMUNICATIONS
(2023)
Article
Chemistry, Multidisciplinary
Ken Yamanomoto, Kota Yamamoto, Satoshi Yoshida, Sota Sato, Takahiko Akiyama
Summary: Quinoline and indole are important core structures, and atropisomeric biaryls consisting of quinoline and indole have unique axially chiral structures. We successfully synthesized 3-(N-indolyl)quinolines with both C-N axial chirality and carbon central chirality, exhibiting high selectivity and good yields.
CHEMICAL COMMUNICATIONS
(2023)
Article
Chemistry, Organic
Tatsuhiro Uchikura, Kazuki Takahashi, Tatsushi Oishi, Takahiko Akiyama
Summary: In this study, an enantioselective intermolecular [2 + 2] photocyclization of alkenyl 2-pyrrolyl ketones using a chiral phosphoric acid was reported. The method allows for the synthesis of cyclobutanes with high enantioselectivity (up to 98% ee). UV-Vis spectra showed a bathochromic shift effect upon mixing the alkenyl 2-pyrrolyl ketones and the chiral phosphoric acid. Non-linear correlation between the ee of the catalyst and the ee of the cycloadduct suggests the formation of a dimer complex between both substrates and the chiral phosphoric acid before photocycloaddition.
ORGANIC & BIOMOLECULAR CHEMISTRY
(2023)
