Article
Chemistry, Organic
Roberto do Carmo Pinheiro, Davi F. Back, Sabrina G. Muller, Cristina Wayne Nogueira, Gilson Zeni
Summary: Base-promoted cyclization reactions have been developed for the synthesis of different benzofurans and benzofuran-fused selenopyrans. The selectivity of the reaction is influenced by the choice of solvent, and specific benzofuran compounds can be prepared using dimethylsulfoxide and potassium tert-butoxide.
JOURNAL OF ORGANIC CHEMISTRY
(2022)
Article
Chemistry, Organic
Rong Wang, Lichen Xu, Yi Lu, Bo Jiang, Wenjuan Hao
Summary: A new Sc(OTf)(3)-catalyzed dearomatization of indole-2-methanols has been reported, providing a series of 3,3'-bisindoles with exocyclic double bond unit in moderate to excellent yields. The importance of the N-sulfonyl group in the dearomatization process was highlighted in the study.
CHINESE JOURNAL OF ORGANIC CHEMISTRY
(2021)
Article
Chemistry, Applied
Jia-Rong Zhang, Hao-Yang Liu, Tao Fan, Yan-Yan Chen, Yan-Li Xu
Summary: A practical method for the synthesis of selenylsubstituted indolo[2,1-a]isoquinolin-6(5H)-ones was developed through Fe(OTf)(3)-promoted tandem selenylation/cyclization of 2-arylindoles, forming new C-Se and C-C bonds simultaneously under mild conditions.
ADVANCED SYNTHESIS & CATALYSIS
(2021)
Article
Chemistry, Organic
Chun-Ting He, Xiao-Li Han, Yan-Xue Zhang, Zhen-Ting Du, Chang-Mei Si, Bang-Guo Wei
Summary: An efficient method has been developed to access functionalized (2,3-dihydroisoxazol-4-yl) ketones by reacting nitrones with ynones or terminal ynones in a one-pot fashion, resulting in moderate to good yields.
ORGANIC & BIOMOLECULAR CHEMISTRY
(2021)
Article
Chemistry, Organic
Shuguang Chen, Langxuan Yang, Yongjia Shang, Jianyou Mao, Patrick J. Walsh
Summary: A novel method for synthesizing 2-azaaryl tetrahydroquinolines is reported by the base-promoted tandem reaction of azaaryl methyl amines and styrene derivatives. Mechanistic probe experiments confirm the mechanism involving deprotonation of the benzylic C-H bond and addition to the styrene vinyl group via the SNAr mechanism. High yields of up to 95% were achieved in over 30 examples, demonstrating the potential applicability of this method.
Article
Chemistry, Organic
Ekaterina S. Spesivaya, Ida A. Lupanova, Dzhamilya N. Konshina, Valery V. Konshin
Summary: An efficient method for the synthesis of tetraalkynylsilanes via the reaction of silicon tetrachloride with different 1-alkynes, promoted by Zn(OTf)(2)/i-Pr2NEt, is reported in this study.
TETRAHEDRON LETTERS
(2021)
Article
Chemistry, Organic
Zhenjie Su, Shaozhong Wang
Summary: An atom-economical protocol utilizing Sc(OTf)3 as the catalyst has been developed to synthesize densely substituted 4acyl-2-quinolones. Mechanistic experimental studies suggest the involvement of coordinative interaction between Sc(OTf)3 and the substrate, formation of an oxetene intermediate, and an electrocyclic ring-opening of the oxetene.
JOURNAL OF ORGANIC CHEMISTRY
(2022)
Article
Chemistry, Organic
Jin-Ming Xie, Yun-Long Zhu, Yan-Ming Fu, Cheng-Feng Zhu, Lan-Jun Cheng, Yang-En You, Xiang Wu, You-Gui Li
Summary: We described a new method for the direct assembly of alpha-(3-indolyl)ketones through the cascade reaction of 2-alkynyl aryl azides with enecarbamates, in which the in situ generated alpha-imino gold carbene intermediate was trapped by enecarbamate to achieve umpolung reactivity of indole at the 3-position.
Article
Chemistry, Multidisciplinary
Yu-Jing Cheng, Liu-Peng Zhao, Lijia Wang, Yong Tang
Summary: Researchers have successfully synthesized Malagasy alkaloids, including four new natural products, using a new synthetic reaction method. These alkaloids show potential for developing cures for malaria and multi-drug resistance. This breakthrough provides a foundation for further chemical and biological exploration.
Article
Chemistry, Organic
Jie Lei, Shi-Qiang Li, Ya-Fei Luo, Dian-Yong Tang, Cheng-He Zhou, Hong-yu Li, Zhi-Gang Xu, Zhong-Zhu Chen
Summary: An efficient one-pot reaction using zinc as catalyst was developed for the rapid synthesis of 2-oxazolines with a wide range of functional groups. Methylene-3-oxazoline was found to play a vital role in initiating the tandem cascade transformation through unfunctionalized alkynes by sequentially adding isocyanide and water. By slightly adjusting the reaction temperature and adding one molecule of water, various beta-amino amide derivatives were synthesized in good to excellent yields.
JOURNAL OF ORGANIC CHEMISTRY
(2022)
Article
Chemistry, Organic
Shuguang Chen, Jiahong Tan, Hao Wu, Quansheng Zhao, Yongjia Shang
Summary: A novel tandem method for synthesizing 2-azaaryl indoline through the reaction of 2-azaaryl methyl amine and 2-fluoro benzyl bromides promoted by LiN(SiMe3)2 was developed. Mechanistic investigation revealed that this cyclization reaction is initiated by selective benzyl C-SN2 substitution followed by an intramolecular SNAr reaction.
ORGANIC & BIOMOLECULAR CHEMISTRY
(2023)
Article
Chemistry, Organic
Sabera Sultana, Peter Yuosef M. Rubio, Hari Datta Khanal, Yong Rok Lee
Summary: This study describes the Sc(OTf)(3)/BF3 center dot OEt2-catalyzed annulation of 3-formylchromones with functionalized alkenes, providing a direct synthetic route to 2-hydroxybenzophenones. The reaction exhibits excellent regio- and chemoselectivities, suitable for late-stage functionalization. Additionally, it proceeds via [3 + 3] and [4 + 2] cycloaddition processes, tolerating various functional groups found in natural terpenes and steroids.
Article
Chemistry, Applied
Yi-En Liang, Chih-Yu Kan, Balaji D. Barve, Yao-Haur Kuo, Hsu-Wei Fang, Wen-Tai Li
Summary: A microwave-assisted, base-promoted, tandem cyclization reaction strategy has been developed for the synthesis of cyclohepta[b]chromones and spiro cyclohepta[b]chromones. This metal-free protocol enables efficient synthesis of diversified cycloheptane-annelated chromones in one-pot reactions, producing a polycyclic ring with a new C-C bond and a new C-O bond.
ADVANCED SYNTHESIS & CATALYSIS
(2022)
Article
Chemistry, Multidisciplinary
Yong Wang, Xinyi Cao, Jingfei Ji, Xiuling Cui, Chao Pi, Leyao Zhao, Yangjie Wu
Summary: The green tandem reaction starting from indoles and diazo compounds utilizes water and fluorinated alcohol as solvent and promoter, respectively, to synthesize 3,3'-bis(indolyl)methanes under metal-free conditions. The sole by-products released are N-2 and water. Absence of water and fluorinated alcohol results in Wolff rearrangement product.
CHINESE CHEMICAL LETTERS
(2021)
Article
Chemistry, Organic
Hongchao Yin, Yuan Tian, Chenxi Guo, Ran Song, Daoshan Yang, Jian Lv
Summary: A facile tandem oxa-Nazarov cyclization and dibromination has been developed, in which the combination of Cu(OTf)2 and diphenyl phosphate (DPP-H) synergistically promotes the coupling of conjugated 1,2-diketones and N-bromosuccinimide, leading to the formation of 2,4-dibromo-3(2H)-furanones in good yields.
JOURNAL OF ORGANIC CHEMISTRY
(2023)
Article
Chemistry, Organic
Ke Gao, Hideki Yorimitsu, Atsuhiro Osuka
EUROPEAN JOURNAL OF ORGANIC CHEMISTRY
(2015)
Article
Chemistry, Multidisciplinary
Ke Gao, Hideki Yorimitsu, Atsuhiro Osuka
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2016)
Article
Chemistry, Multidisciplinary
Ke Gao, Norihito Fukui, Seok Ii Jung, Hideki Yorimitsu, Dongho Kim, Atsuhiro Osuka
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2016)
Article
Chemistry, Organic
Ke Gao, Shinya Otsuka, Alexandre Baralle, Keisuke Nogi, Hideki Yorimitsu, Atsuhiro Osuka
JOURNAL OF SYNTHETIC ORGANIC CHEMISTRY JAPAN
(2016)
Review
Chemistry, Multidisciplinary
Ke Gao, Naohiko Yoshikai
ACCOUNTS OF CHEMICAL RESEARCH
(2014)
Article
Chemistry, Applied
Ke Gao, Rupankar Paira, Naohiko Yoshikai
ADVANCED SYNTHESIS & CATALYSIS
(2014)
Article
Chemistry, Multidisciplinary
Naohiko Yoshikai, Ke Gao
PURE AND APPLIED CHEMISTRY
(2014)
Article
Chemistry, Organic
Ke Gao, Takeshi Yamakawa, Naohiko Yoshikai
SYNTHESIS-STUTTGART
(2014)
Article
Chemistry, Organic
Ninglin Li, Fuqiang Xiong, Ke Gao
Summary: An efficient cobalt-based catalytic system has been developed for the protodeboronation of various aryl and vinyl boronates, tolerating a wide range of functional groups. Additionally, the reaction has been extended to deuterodeboronation with D2O, offering a potential protocol for the synthesis of regiospecifically deuterated arenes and olefins.
JOURNAL OF ORGANIC CHEMISTRY
(2021)
Article
Chemistry, Organic
Yanmeng Zhang, He Zhang, Ke Gao
Summary: The study demonstrates the use of a borane-trimethylamine complex as an efficient reducing agent for selective methylation and formylation of amines with 1 atm CO2 under metal-free conditions. 6-Amino-2-picoline proved to be a highly efficient catalyst for the methylation of various secondary amines. Mechanistic studies indicate that the 6-amino-2-picoline-borane catalytic system operates similarly to an intramolecular frustrated Lewis pair for CO2 activation.
Article
Chemistry, Organic
Yulin Sun, Ke Gao
Summary: An inexpensive and efficient method for the synthesis of various functionalized benzimidazoles, benzoxazole, and benzothiazole through a CO2-mediated reductive cyclization reaction in the presence of triethoxysilane is described. Mechanistic studies reveal that formic acid acts as a cocatalyst to promote the cyclization reaction.
JOURNAL OF ORGANIC CHEMISTRY
(2023)
Article
Chemistry, Multidisciplinary
Wei Xiong, Xuan Jiang, Wen-Cheng Wang, Ying Cheng, Liang-Qiu Lu, Ke Gao, Wen-Jing Xiao
Summary: Conjugate addition is a crucial method for synthesizing carbon skeletons and has been widely used in the synthesis of natural products and drugs. However, asymmetric catalysis studies have primarily focused on the construction of stereogenic centers from conjugate alkenes. In this study, we describe the first photoinduced cobalt-catalyzed dynamic kinetic reductive conjugate addition reaction that allows for the formation of heterobiaryls with axial chirality (45 examples, with yields up to 91% and enantiomeric excess of 97%). This method offers mild reaction conditions, good tolerance to various functional groups, and excellent control over enantiomeric outcomes. Importantly, it eliminates the generation of large amounts of metal waste and the need for precious metal catalysts. Kinetic studies suggest that the migration of the chiral arylcobalt species into the alkene may be the rate-determining step.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2023)
Article
Chemistry, Organic
He Zhang, Yanmeng Zhang, Ke Gao
Summary: The selective reductive N-methylation and N,N-dimethylation of primary amines using CO2 is challenging. This study reports a highly selective N,N'-diisopropylcarbodiimide-catalyzed methylation of primary amines using 1 atm CO2 under metal-free conditions. The selectivity of methylation is controlled by the steric effects of amines and boranes.
ORGANIC CHEMISTRY FRONTIERS
(2023)
Article
Chemistry, Organic
Fuqiang Xiong, Qi Cheng, Yanfeng Dang, Ke Gao
Summary: In this study, a four-component reductive methylation reaction catalyzed by 2-Aminothiazole in combination with a borane-trimethylamine complex was proposed. Highly functionalized tertiary N-methylamines were efficiently synthesized in one pot using this reaction. This method is not only applicable to the gram-scale synthesis of butenafine, but also suitable for late-stage modifications of several drugs.
ORGANIC CHEMISTRY FRONTIERS
(2022)
Article
Chemistry, Organic
Rongpei Wu, Ke Gao
Summary: A highly efficient method for tandem protonation/deuteration and reduction of enamines in the presence of water and pinacolborane was developed, achieving regioselective beta-deuteration of tertiary amines. D2O was used as a readily available and cheap source of deuterium. Mechanistic studies showed that B(C6F5)(3) could activate water to promote the protonation and reduction of enamines.
ORGANIC & BIOMOLECULAR CHEMISTRY
(2021)
