Article
Chemistry, Organic
Yoon Sung Cho, Seung Tae Kim, Do Hyun Ryu
Summary: A chiral Lewis acid-catalyzed enantioselective Friedel-Crafts alkylation using in situ-generated o-quinone methides has been developed. The reaction showed high yield (up to 99%) and excellent enantioselectivity (up to >99% ee) in the presence of a chiral oxazaborolidinium ion catalyst.
Article
Chemistry, Organic
Naifu Zhou, Junhao Zhao, Chengbo Sun, Yuqin Lai, Zhixiong Ruan, Pengju Feng
Summary: A practical protocol for synthesizing 3-substituent-2-(azol-1-yl)indole derivatives has been developed through an electrochemical oxidative cross coupling process. This strategy tolerates a variety of functional groups and is suitable for gram scale synthesis, as well as late-stage functionalization of bioactive molecules.
JOURNAL OF ORGANIC CHEMISTRY
(2021)
Review
Chemistry, Multidisciplinary
Giovanni Centonze, Chiara Portolani, Paolo Righi, Giorgio Bencivenni
Summary: Axially chiral compounds, once viewed as merely a laboratory curiosity, have gained recognition in the past two decades for their significant role in medicinal, biological, and material chemistry. The asymmetric synthesis of atropisomers, particularly N-N atropisomers, has become a rapidly expanding field with new challenges and frontiers. This review highlights recent advances and breakthroughs in the enantioselective synthesis of N-N atropisomers, showcasing the strategies and frameworks involved.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Organic
Wan-Zhen Li, Wei Zhang, Xiao-Hui Chen, Zhao-Dong Wang, Hai-Lei Cui
Summary: A convenient synthesis method for methylene-bridged pyrrolo[2,1-a]isoquinolines has been developed, yielding bispyrroloisoquinolylmethanes and bispyrrolylmethanes in good yields. This synthesis method also allows for easy chemical transformation of the methylene-bridged pyrroloisoquinoline, providing unsymmetric acids and amides with a privileged framework.
JOURNAL OF ORGANIC CHEMISTRY
(2022)
Article
Chemistry, Medicinal
Changjun Yu, Ruiyao E., Xiao-Wei Zhang, Wen-Qian Hu, Guangjun Bao, Yiping Li, Yuyang Liu, Zeyuan He, Jingyue Li, Wen Ma, Ling-Yun Mou, Rui Wang, Wangsheng Sun
Summary: Innovations in synthetic chemistry play a crucial role in drug discovery and development. Developing simple and effective methods for synthesizing medicinal modules is of great significance. In this study, we successfully developed a NaClO-mediated cross installation of indoles and azoles, which are commonly found in drugs and natural products. This method provides a convenient route for accessing a library of N-linked 2-(azol-1-yl) indole derivatives and allows late-stage modification of drugs, natural products, and peptides. Furthermore, the biological screening of the library demonstrated promising anticancer activities against A549 and NCI-H1975 cells, providing a potential lead for anticancer drug discovery.
Article
Chemistry, Organic
Wesley J. Olivier, Alex C. Bissember, Jason A. Smith
Summary: The total syntheses of Stemona alkaloids sessilifoliamides B and D, as well as the second synthesis of sessilifoliamide C, were successfully completed from a simple pyrrole substrate. The bicyclic lactam core was prepared on a gram scale via a Bronsted acid mediated cyclization and controlled oxidation with Dess-Martin periodinane. Yield percentages for the synthesis of sessilifoliamides B, C, and D were 24%, 13%, and 17% respectively, over multiple steps.
Article
Chemistry, Organic
Ferdinand Taenzler, Jiasu Xu, Sudhakar Athe, Viresh H. Rawal
Summary: This article presents the dearomative (4 + 3) cycloaddition reactions of 3-alkenylindoles with in situ-generated oxyallyl cations, as well as the transformation of the resulting cycloadducts and preliminary investigations into their enantioselective catalysis using imidodiphosphorimidate catalysts.
Article
Chemistry, Multidisciplinary
Xueting Zhou, Qingqin Huang, Jiami Guo, Lei Dai, Yixin Lu
Summary: A new molecular editing method called skeletal recasting strategy is developed to synthesize fully substituted pyrroles from simple pyrroles through dearomative deconstruction and rearomative reconstruction steps, leading to the synthesis of challenging tetra-substituted pyrroles and anticancer drug Sutent.
ACS CENTRAL SCIENCE
(2023)
Article
Chemistry, Organic
Arben Berisa, Matija Gredicak
Summary: This paper describes the enantioselective reaction between 2,5-disubstituted pyrroles and diaryl-ketimines generated from isoindolinone-derived alcohols. Pyrrole derivatives with a congested tetrasubstituted stereogenic center at the beta-(C3) position are obtained in high yields and enantioselectivities. The reaction can also be extended to 2-monosubstituted pyrroles, producing chiral alpha-(C5) functionalized pyrrole products. Control experiments were conducted to explain the origin of low enantioselectivities in some products.
ORGANIC & BIOMOLECULAR CHEMISTRY
(2023)
Article
Chemistry, Organic
Shuo Wang, Shi-Jie Ma, Ji-Cong Lou, Wen-Wu Sun, Bin Wu
Summary: The copper-catalyzed cycloaddition reaction of N-hydroxysuccinimide ester and isocyanatoacetate was reported, resulting in a series of 4,5-disubstituted oxazole compounds, including those derived from natural fatty acids, drugs, amino acids, and peptides, with moderate to high yields. The derivatization reaction and mechanism were also explored.
JOURNAL OF ORGANIC CHEMISTRY
(2023)
Article
Chemistry, Multidisciplinary
Fernanda Liu, Lakshita Anand, Michal Szostak
Summary: Skeletal editing through single-atom insertion reactions involving nitrogen heterocycles has been reported, utilizing electrophilic carbonyl cation equivalents and in situ generated nitrenes. This methodology enables transformation of pyrroles and indoles to pyridines, quinolines, and quinazolines, offering an innovative approach to complex molecular structures by heterocycle diversification and peripheral editing. Considering the significance of heterocycles in medicinal chemistry, biology, and natural products, these methods provide a valuable tool for molecular editing.
CHEMISTRY-A EUROPEAN JOURNAL
(2023)
Article
Chemistry, Organic
Jia Seo, Che-Wei Chen, Woohyeong Lee, Ju Eun Jeon, Pei-Ling Chen, Shih-Ching Chuang, Jung Min Joo
Summary: A benzannulation strategy was developed involving activation of two C-H bonds of five-membered heteroarenes, resulting in fluorescent benzofuran and indole derivatives through Pd-catalyzed oxidative reactions. This strategy provides a potential pathway for further development of functionalized polycyclic heteroaromatic compounds.
SYNTHESIS-STUTTGART
(2021)
Article
Chemistry, Multidisciplinary
Leiqing Fu, Jie-Ping Wan, Liyun Zhou, Yunyun Liu
Summary: In this study, a copper-catalyzed annulation of enaminones with alkynyl esters was developed for the synthesis of different pyrroles with a 2,3,4,5-tetrasubstituted structure. By using Cu(OAc)(2) as the catalyst, the synthesis of 2-vinyl and 2,3-dicarboxyl-functionalized pyrroles was achieved using terminal and internal alkynyl esters, respectively. The synthesis of 2-vinyl pyrroles represents the first example of accessing 2-vinyl substituted pyrroles via direct cascade reactions involving vinylation and pyrrole ring formation.
CHEMICAL COMMUNICATIONS
(2022)
Article
Chemistry, Multidisciplinary
Rahul A. Jagtap, Benudhar Punji
Summary: The paper summarizes the developments in nickel-catalyzed regioselective functionalization of azoles and indoles, with a particular focus on the reaction mechanism.
Article
Chemistry, Organic
Mrinmay Baidya, Jhilik Dutta, Suman De Sarkar
Summary: Intramolecular electro-oxidative addition of enamines or amides to nonactivated alkynes was achieved to obtain carbonyl-pyrroles or-oxazoles from N-propargyl derivatives. Organoselenium was used as the electrocatalyst, functioning as a pi-Lewis acid to selectively activate the alkyne for successful nucleophilic addition. The synthetic strategy allows for a wide range of substrate scope with up to 93% yield. Several mechanistic experiments, including the isolation of a selenium-incorporated intermediate adduct, shed light on the electrocatalytic pathway.
Review
Chemistry, Organic
Kotaro Kikushima, Ravi Kumar, Toshifumi Dohi
Summary: The use of [F-18]-labeled drugs and radioligands is common in PET radiopharmaceuticals for clinical and preclinical research. Various methods for introducing [F-18]fluorine into complex molecules through fluorination reactions have been reported. Recent advances in [F-18]-fluorination using aryliodonium(III) compounds are highlighted in this study.
MINI-REVIEWS IN ORGANIC CHEMISTRY
(2021)
Article
Biochemistry & Molecular Biology
Kotaro Kikushima, Haruka Koyama, Kazuki Kodama, Toshifumi Dohi
Summary: The study demonstrates metal-free synthesis of monosubstituted aromatic compounds via nucleophilic aromatic substitution reactions, resulting in functionalized PTH derivatives through two-step reactions, some of which show potential application as photocatalysts for carbon-halogen bond reduction.
Review
Chemistry, Multidisciplinary
Ravi Kumar, Fateh V. Singh, Naoko Takenaga, Toshifumi Dohi
Summary: The review focuses on asymmetric oxidative dearomatization reactions involving hypervalent iodine compounds, summarizing asymmetric intra- and intermolecular dearomatization reactions using chiral hypervalent iodine reagents/catalysts as well as hypervalent iodine-mediated dearomatization reactions followed by desymmetrization.
CHEMISTRY-AN ASIAN JOURNAL
(2022)
Review
Chemistry, Organic
Kotaro Kikushima, Elghareeb E. Elboray, J. Oscar C. Jimenez-Halla, Cesar R. Solorio-Alvarado, Toshifumi Dohi
Summary: This review summarizes the double functionalization of carbon-iodine(iii) and ortho carbon-hydrogen bonds using diaryliodonium(iii) salts, which has significant application value in molecular synthesis.
ORGANIC & BIOMOLECULAR CHEMISTRY
(2022)
Article
Chemistry, Organic
Tohru Kamitanaka, Yusuke Tsunoda, Yuriko Fujita, Toshifumi Dohi, Yasuyuki Kita
Summary: The synthesis of 2-oxygenated dihydrobenzofurans via [3 + 2] coupling of quinone monoacetals with vinyl ethers has been achieved using tetrabutylammonium triflate catalysis. This new method involves activating the acetal moiety in quinone monoacetals under acid-free conditions to obtain highly oxygenated dihydrobenzofurans, with triflate anion catalyst stabilizing the cationic intermediate.
Article
Chemistry, Organic
Kotaro Kikushima, Naoki Miyamoto, Kazuma Watanabe, Daichi Koseki, Yasuyuki Kita, Toshifumi Dohi
Summary: High reactivity of trimethoxyphenyl (TMP)-iodonium(III) acetate was achieved for phenol O-arylation. The cooperation of TMP ligand and acetate anion enhances the electrophilic reactivity towards phenol oxygen atoms. This ligand- and counterion-assisted strategy shows high applicability with tolerance towards various functional groups.
Review
Chemistry, Organic
Rimi, Sakshi Soni, Bhawna Uttam, Hideyasu China, Toshifumi Dohi, Viktor V. Zhdankin, Ravi Kumar
SYNTHESIS-STUTTGART
(2022)
Review
Biochemistry & Molecular Biology
Samata E. Shetgaonkar, Ritu Mamgain, Kotaro Kikushima, Toshifumi Dohi, Fateh V. Singh
Summary: The chemistry of polyvalent iodine compounds has attracted researchers' interest due to their role as important and flexible reagents in synthetic organic chemistry, leading to the production of various useful organic molecules. These chemicals have potential applications in functionalization processes due to their non-toxic and environmentally friendly properties. Recent research has focused on the use of hypervalent iodine reagents in palladium-catalyzed transformations, particularly in C-H bond functionalization. The article provides a detailed review of the recent advances in palladium-catalyzed oxidative cross-coupling reactions employing hypervalent iodine reagents.
Article
Chemistry, Organic
Koji Morimoto, Kana Yanase, Kentaro Toda, Hitoshi Takeuchi, Toshifumi Dohi, Yasuyuki Kita
Summary: In this study, a metal-free cross-dehydrogenative coupling of phenols and anilines with phenothiazines was achieved using hypervalent iodine reagents. The method allowed selective amination products to be obtained under mild conditions. The reaction proceeded efficiently at previously unreported 20 degrees C for aniline amination.
Article
Chemistry, Organic
Kotaro Kikushima, Aki Morita, Elghareeb E. Elboray, Taeho Bae, Naoki Miyamoto, Yasuyuki Kita, Toshifumi Dohi
Summary: TMP-iodonium(III) acetate serves as an efficient arylation reagent for N,O-protected hydroxylamines, generating aniline derivatives without the need for transition metal catalysts. The amination reaction is compatible with various protecting groups, producing versatile synthetic intermediates for functional organic molecules.
SYNTHESIS-STUTTGART
(2022)
Article
Chemistry, Multidisciplinary
Kotaro Kikushima, Kohei Yamada, Narumi Umekawa, Natsumi Yoshio, Yasuyuki Kita, Toshifumi Dohi
Summary: Catalyst-free access to aryldifluoromethyl ketones has been achieved through decarboxylative arylation of alpha,alpha-difluoro-beta-ketoacid salts using diaryliodonium(iii) salts. The products were successfully transformed into the corresponding esters, amides, and difluoromethyl compounds. This strategy provides access to fluorine-containing drugs, thus contributing to drug design.
Article
Chemistry, Applied
Elghareeb E. Elboray, Taeho Bae, Kotaro Kikushima, Yasuyuki Kita, Toshifumi Dohi
Summary: We developed a metal catalyst-free protocol for O-arylation of benzamide hydroxamate esters. By varying the electronic and/or steric properties of the diaryliodonium salt and/or the substrate, the chemoselective O- versus N-arylation of the amides was controlled. The O-arylation reaction showed preference for sterically and electronically diverse substrates. This study demonstrates the possibility of substituent- and reagent-controlled chemoselectivity with diaryliodonium salts and may draw interest in the field of hypervalent iodine chemistry.
ADVANCED SYNTHESIS & CATALYSIS
(2023)
Article
Chemistry, Multidisciplinary
Mohammed F. F. Radwan, Elghareeb E. E. Elboray, Hemat M. M. Dardeer, Yusuke Kobayashi, Takumi Furuta, Shohei Hamada, Toshifumi Dohi, Moustafa F. F. Aly
Summary: 1,3-Dipolar cycloaddition through in situ generation of azomethine ylide provides a straightforward and critically important sustainable approach for access to diverse pyrrolidine chemical space. Metal-free AcOH-activated 1,3-dipolar cycloaddition protocol was developed to synthesize uncommon pyrrolidine cycloadducts with excellent diastereoselectivity. The reaction mechanism and the key role of AcOH were supported by experimental, theoretical and spectroscopic studies.
CHEMISTRY-AN ASIAN JOURNAL
(2023)
Review
Biochemistry & Molecular Biology
Samata E. Shetgaonkar, Subhiksha Jothish, Toshifumi Dohi, Fateh V. Singh
Summary: The chemistry of hypervalent iodine reagents has become valuable due to their reactivity under mild reaction conditions and resemblance to transition metals. These environmentally friendly reagents are suitable for Green Chemistry. Iodine(V) reagents, such as IBX and DMP, have been used as oxidants in organic synthesis either stoichiometrically or catalytically. This review article describes various oxidation reactions induced by iodine(V) reagents reported in the past decade.
Review
Chemistry, Organic
Luis A. Segura-Quezada, Karina R. Torres-Carbajal, Kevin A. Juarez-Ornelas, Angel J. Alonso-Castro, Rafael Ortiz-Alvarado, Toshifumi Dohi, Cesar R. Solorio-Alvarado
Summary: Iodine (III) reagents, with their characteristics of safety, environmental friendliness, and ease of use, have become important alternatives in organic synthesis. They have been widely used in the functionalization of various aromatic cores, introducing multiple functional groups. Furthermore, iodine (III) reagents have significant applications in metal-free arylation reactions.
ORGANIC & BIOMOLECULAR CHEMISTRY
(2022)
