Article
Chemistry, Organic
Shanguang Qiu, Yuxue Chen, Xinming Song, Li Liu, Xi Liu, Luyong Wu
Summary: In this study, intermolecular cycloaddition of tosylhydrazones with nitriles was investigated. t-BuOK was found to be an excellent base for increasing reaction effectiveness, while using xylene as a solvent significantly inhibited homocoupling of the tosylhydrazones. As a result, a variety of 4,5-diaryl-2H-1,2,3-triazoles were prepared in good to excellent yields and high purities, with the process being azide-free and transition-metal-free.
Article
Chemistry, Organic
Yuanjing Huang, Jing Zhang
Summary: In this study, a practical and efficient KOtBu-facilitated amination of carboxylic acids with N,N-dimethylamine was described. This method is applicable for the transformation of various aliphatic and aromatic carboxylic acids and can be used for the late-stage dimethylamidation of complex drug molecules.
SYNTHESIS-STUTTGART
(2022)
Review
Chemistry, Organic
Zhang Lizhi, Liao Yongjian, Chen Ning, Huang Lei, Zhou Min
Summary: Transition metal-catalyzed reactions and non-metal-promoted chemical bond construction reactions are two important research directions in the field of chemistry. The potassium tert-butoxide-promoted cyclization and coupling reactions have rapidly developed in recent years, providing new tools and ideas for green chemistry development.
CHINESE JOURNAL OF ORGANIC CHEMISTRY
(2022)
Article
Chemistry, Organic
Hye Sung Yang, Lingamurthy Macha, Hyun-Joon Ha, Jung Woon Yang
Summary: The study confirmed that 1,3-chelation and the formation of a tetrahedral intermediate play crucial roles in the unusual nucleophilic behavior of a metal t-butoxide in a transesterification reaction. Mechanistic investigations using NMR and real-time IR spectroscopies demonstrated the possibility of achieving value-added reactions based on the understanding of the t-butoxide anion action.
ORGANIC CHEMISTRY FRONTIERS
(2021)
Article
Chemistry, Organic
Shang Wang, Yunfei Xiang, Tiantian Chen, Xiang Wu, Dong Xing
Summary: A KOtBu-catalyzed alpha-homoallylic alkylation of lactams with 1,3-dienes is reported in this study. This transition metal-free and atom-economical protocol allows for the formation of alpha-homoallylic alkylated lactams bearing alpha-quaternary carbon centers with excellent regioselectivity. A proposed cation-pi interaction between the in situ-generated potassium enolate and the diene plays a key role in accelerating this transformation.
ORGANIC CHEMISTRY FRONTIERS
(2022)
Article
Chemistry, Multidisciplinary
Yucheng Yin, Lijing Leng, Xiaolong Lin, Yan Yu, Tian Cai, Qunli Luo
Summary: Bridged isoquinoline derivatives are important in bioactive molecules. Previous studies have focused on the synthesis of 1,3-bridged cyclic skeletons, but we report the first synthesis of 1,4-bridged dihydroisoquinolin-3-ones. We successfully inhibited the O-nucleophilic substitution of cyclic 1,3-diketones and obtained the desired product.
ACTA CHIMICA SINICA
(2022)
Article
Chemistry, Organic
Mizuki Yamazaki, Tomoyuki Yoshimura, Jun-ichi Matsuo
Summary: 1,3-Cyclobutanediones reacted with aromatic aldehydes to produce cyclic beta-keto esters, catalyzed by a small amount of potassium ethoxide. The effects of alkoxide catalysts and spiro cyclic groups on the 1,3-cyclobutanediones were examined.
TETRAHEDRON LETTERS
(2021)
Article
Chemistry, Inorganic & Nuclear
Feng Wen-Qin, Li Chao, Liu Kai-Yuan, Cai Ming-Yuan, Fan Mei-Qiang
Summary: The addition of C4H9OK significantly enhances the hydrogen storage properties of the Mg(NH2)(2)-2LiH system, leading to lower dehydrogenation temperature and improved hydrogen absorption rate and capacity. This enhancement is attributed to the decreased activation energy and reaction enthalpy, as well as improved kinetic and thermodynamic properties facilitated by C4H9OK catalysis and participation in reactions.
CHINESE JOURNAL OF INORGANIC CHEMISTRY
(2021)
Article
Chemistry, Multidisciplinary
Ahmed Y. Nuriye, Joseph Barr
Summary: The iodine-promoted dimerization of enolates of methyl 2-arylacetates generated with tBuOK under equilibrium conditions is reported. The oxidative homocoupling reaction yields a mixture of dl and meso dimers with moderate to good yields and diastereoselectivity. Electron-withdrawing substituents on the aryl ring appear to facilitate dimerization for higher yields, and ortho-substituted aryl acetates provide better diastereoselectivity.
RESULTS IN CHEMISTRY
(2022)
Article
Chemistry, Organic
Zhiwei Ma, Xiaopei Chen, Chuanchuan Wang, Jianling Wang, Jingchao Tao, Quanjian Lu
Summary: A stereoselective methodology has been developed to construct synthetically and pharmaceutically useful chiral chromene derivatives with high yields and enantioselectivities.
CHINESE JOURNAL OF ORGANIC CHEMISTRY
(2022)
Article
Chemistry, Organic
Jie Feng, Qiaoling Zhang, Fuhai Li, Lu Yang, Ratnakar Reddy Kuchukulla, Qingle Zeng
Summary: A transition-metal-free reductive C-P cross-coupling reaction of arylvinyl sulfides with diarylphosphine oxides has been developed, allowing the synthesis of diaryl(2-arylethyl)phosphine oxides and the construction of a C-P bond through C-S bond cleavage and reduction of a C-C double bond in one pot.
Article
Chemistry, Organic
Mahalingam Sivaraman, Sivakalai Mayakrishnan, Chandrasekar Balachandran, Shin Aoki, Narayanan Uma Maheswari, Paramasivan T. Perumal
Summary: Privileged indole-fused phenanthridinones were efficiently synthesized via a potassium tert-butoxide-promoted intramolecular radical cyclization reaction. The synthesized compounds exhibited excellent photoluminescence properties and were successfully used as fluorescent bioprobes for live cancer cell imaging.
Article
Chemistry, Multidisciplinary
A. S. Soldatenko, N. F. Lazareva
Summary: In this study, the first representatives of cyclic azobenzene-siloxane hybrid compounds were successfully synthesized, including two new compounds.
RUSSIAN CHEMICAL BULLETIN
(2021)
Article
Chemistry, Organic
A. M. Galeeva, Z. R. Valiullina, N. K. Selezneva, M. S. Miftakhov
Summary: The study investigated the transformations of 2,3-dibromo-2-methylpropanamides with different substituents on the nitrogen atom by potassium tert-butoxide in THF. Results showed that the amount of t-BuOK significantly affected the yield and selectivity of the products.
RUSSIAN JOURNAL OF ORGANIC CHEMISTRY
(2021)
Article
Chemistry, Organic
Mizuki Yamazaki, Tomoyuki Yoshimura, Jun-ichi Matsuo
Summary: 1,3-Cyclobutanediones reacted with aromatic aldehydes to produce cyclic beta-keto esters, catalyzed by a small amount of potassium ethoxide. The effects of alkoxide catalysts and spiro cyclic groups on the 1,3-cyclobutanediones were examined.
TETRAHEDRON LETTERS
(2021)
Article
Chemistry, Organic
Hironori Takeuchi, Yusuke Fujimori, Yoshihiro Ueda, Hiromitsu Shibayama, Masaru Nagaishi, Tomoyuki Yoshimura, Takahiro Sasamori, Norihiro Tokitoh, Takumi Furuta, Takeo Kawabata
Article
Biochemistry & Molecular Biology
Misa Nishiyama, Noritaka Nakamichi, Tomoyuki Yoshimura, Yusuke Masuo, Tomoe Komori, Takahiro Ishimoto, Jun-ichi Matsuo, Yukio Kato
NEUROCHEMICAL RESEARCH
(2020)
Article
Chemistry, Organic
Tomoyuki Yoshimura, Yuki Enami, Jun-ichi Matsuo
SYNTHESIS-STUTTGART
(2020)
Article
Chemistry, Medicinal
Tomoyuki Yoshimura, Yuki Umeda, Risako Takahashi, Jun-ichi Matsuo
CHEMICAL & PHARMACEUTICAL BULLETIN
(2020)
Article
Chemistry, Medicinal
Mika Hanashima, Toshiki Matsumura, Yuta Asaji, Tomoyuki Yoshimura, Jun-ichi Matsuo
CHEMICAL & PHARMACEUTICAL BULLETIN
(2020)
Article
Chemistry, Organic
Kenta Sakamoto, Yuya Ikawa, Tomoyuki Yoshimura, Jun-ichi Matsuo
Summary: Metal-free cyclopropanation of N-protected indoles with alpha-aryl-alpha-diazoacetates was successfully achieved using triflic imide as a Bronsted acid catalyst. The addition of a catalytic amount of methyl phenylacetate improved the efficiency of the reaction. A proposed reaction mechanism involving C-protonation of diazoacetates with HNTf2, followed by formal [3+2] cycloaddition with indoles and 1,3-rearrangement, explains the success of the cyclopropanation reaction.
EUROPEAN JOURNAL OF ORGANIC CHEMISTRY
(2021)
Article
Multidisciplinary Sciences
Ayumi Imayoshi, Bhatraju Vasantha Lakshmi, Yoshihiro Ueda, Tomoyuki Yoshimura, Aki Matayoshi, Takumi Furuta, Takeo Kawabata
Summary: Since the discovery of mechanically planar chiral rotaxanes and topologically chiral catenanes, their asymmetric synthesis has been a long-standing challenge. Here, the authors report enantioselective preparation of mechanically planar chiral rotaxanes with up to 99.9% ee in 29% yield.
NATURE COMMUNICATIONS
(2021)
Article
Chemistry, Organic
Tomoyuki Yoshimura, Kanta Chino, Jun-ichi Matsuo
Summary: A novel and concise synthesis method for 1,3,5-cycloheptatrienes has been developed, which can be achieved through mild reaction conditions and simple manipulations. The synthesis is advantageous due to its use of readily available reagents and moderate yields of the desired products.
TETRAHEDRON LETTERS
(2021)
Article
Chemistry, Organic
Fuka Hori, Tomoyuki Yoshimura, Jun-ichi Matsuo
Summary: A novel method for the synthesis of 3-alkyl-2-arylindoles was developed through sequential oxidation and reduction reactions. Starting from 2-(2-nitrophenyl)ethanols prepared by a base-catalyzed three-component reaction, the desired products were obtained by oxidation and reduction steps. Notably, a selective synthesis of N-hydroxyindole was also achieved. Furthermore, the highly nucleophilic nature of transient benzylic anions in DMSO was demonstrated for the three-component reactions.
Article
Chemistry, Organic
Tomoyuki Yoshimura, Ken-ichi Onda, Jun-ichi Matsuo
Summary: An asymmetric synthesis method using an axially chiral arylaryne intermediate has been developed, which allows for the formation of chiral biaryl compounds while preserving the enantiomeric excess (ee) of the precursor. The high chiral transfer from precursor to product was observed at both low and room temperature.
Article
Chemistry, Organic
Tomoka Dentani, Ayano Kawachi, Misaki Kato, Tomoyuki Yoshimura, Jun-ichi Matsuo
Summary: In this study, the regioselectivity and stereoselectivity of intramolecular domino aldol cyclization/acetalizations of 1,2,7,8-tetraones were investigated using various catalytic agents. Good enantioselectivities were observed in the direct catalytic asymmetric cyclization of a 1,2,7,8-tetraone with chiral organocatalysts. Furthermore, the total synthesis of (+/-)-nesteretal A, a highly oxidized cage molecule, was accomplished using TiCl4-promoted anti-selective aldol cyclization of a symmetrical 1,2,7,8-tetraone as the key reaction.
ORGANIC CHEMISTRY FRONTIERS
(2022)
Article
Chemistry, Multidisciplinary
Shunya Morita, Tomoyuki Yoshimura, Jun-ichi Matsuo
Summary: The three-component reactions of nitroalkanes, acrylamides, and aldehydes using catalytic amount of KOH in DMSO resulted in the formation of beta '-hydroxy-gamma-nitro amides. Mechanistic studies showed that the reactions proceeded through domino Michael/aldol reactions.
Article
Chemistry, Organic
Pan Yang, Tomoyuki Yoshimura, Takahiro Sasamori, Norihiro Tokitoh, Kazuhiro Morisaki, Takeo Kawabata
