Article
Chemistry, Physical
Jose A. Carmona, Carlos Rodriguez-Franco, Joaquin Lopez-Serrano, Abel Ros, Javier Iglesias-Siguenza, Rosario Fernandez, Jose M. Lassaletta, Valentin Hornillos
Summary: An efficient dynamic kinetic resolution (DKR) approach has been developed for the synthesis of axially chiral diamines based on ruthenium-catalyzed enantioselective transfer hydrogenation. This method features a broad substrate scope and proceeds under very mild conditions, allowing the preparation of BINAM homologues in good to high yields and nearly perfect enantioselectivities (up to 99% ee).
Article
Chemistry, Multidisciplinary
Yuanyuan Li, Longhui Duan, Biqiong Hong, Zhenhua Gu
Summary: This study developed a copper-catalyzed enantioselective ring-opening reaction, which can selectively advance the synthesis of different functionalized compounds starting from 2,2'-dibromo-6,6'-diiodo-1,1'-biphenyl. Through a series of functionalization reactions, a new and convenient approach for synthesizing functionalized axially chiral biphenyls was introduced.
CHINESE JOURNAL OF CHEMISTRY
(2023)
Article
Chemistry, Multidisciplinary
Yan-Bo Li, Hu Tian, Shuai Zhang, Jun-Zhao Xiao, Liang Yin
Summary: In this study, a copper(I)-catalyzed reaction of diarylphosphines and O-benzoyl hydroxylamines was developed, leading to the synthesis of aminophosphinites and P-chiral aminophosphinites. The reaction mechanism was proposed and further transformation to P-chiral phosphines was achieved.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Chemistry, Physical
Yingqi Xia, Yingtang Ning, Minjie Liu, Fen -Er Chen
Summary: A poly(ethylene glycol) supported amino alcohol has been developed as a chiral ligand for the copper-catalyzed asymmetric nitrolaldol reaction. The catalyst enables the synthesis of syn-2-nitro-1,3-diols with high yields and stereoselectivities. The PEG moiety allows for easy purification and recycling of the catalyst.
JOURNAL OF CATALYSIS
(2023)
Review
Chemistry, Multidisciplinary
Hong-Hao Zhang, Tian-Zhen Li, Si-Jia Liu, Feng Shi
Summary: The catalytic asymmetric synthesis of atropisomers bearing multiple chiral elements has recently become an emerging research field. Chemists have devised metal-catalyzed or organocatalytic asymmetric reactions for accessing atropisomers with multiple chiral elements, such as those with center chirality, planar chirality, and helical chirality. This review summarizes the rapid developments in this field and indicated the remaining challenges.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Applied
Liang Xu, Jia Cui, Shan Gao, Jianjun Wang, Jiao Liu, Hongge Jia, Zhuanfang Zhang, Fengjuan Miao, Yu Zang
Summary: Chiral conjugated microporous polymers (CCMPs) containing amide groups were designed and synthesized for the first time as heterogeneous asymmetric catalyst platforms for the stabilization of Pd in asymmetric catalytic synthesis. Four Pd/CCMPs heterogeneous catalysts exhibited efficient catalytic activity and excellent enantioselectivity in the asymmetric Henry reaction, with a wide range of substrates and easy recovery. The Pd/CCMPs composites could be easily recycled and maintained catalytic activity after 3 cycles of reactions.
MICROPOROUS AND MESOPOROUS MATERIALS
(2022)
Article
Chemistry, Multidisciplinary
Chenlu He, Yan Li
Summary: This article reviews the historical research on circularly polarized light (CPL)-induced absolute asymmetric synthesis, including chiral organic molecules, helical polymers, supramolecular assemblies, and noble metal nanostructures. However, based on these results, it is concluded that the chiral photon-matter interaction is very weak, resulting in a very small enantiomeric excess for the product. Therefore, the recently emerged superchiral field technology, which can enhance the dissymmetry of the optical field and near-field, is highlighted.
CHINESE CHEMICAL LETTERS
(2023)
Article
Chemistry, Multidisciplinary
Jialin Qi, Fang Wei, Shuai Huang, Chen-Ho Tung, Zhenghu Xu
Summary: A new method has been developed for the synthesis of sulfur-containing chiral beta-lactams with two consecutive stereogenic centers using copper(I)-catalyzed asymmetric, three-component interrupted Kinugasa reaction. The key lies in the interception of in situ formed chiral four membered copper(I) enolate intermediate with sulfur electrophiles, resulting in good yields and excellent diastereo- and enantioselectivity.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2021)
Article
Chemistry, Multidisciplinary
Mingkang Zhou, Yaodong Lin, Xiao-Xuan Chen, Guangqing Xu, Lung Wa Chung, Wenjun Tang
Summary: We report the chiral diboron-templated asymmetric homocoupling of aryl alkyl ketimines, leading to the formation of chiral vicinal tetrasubstituted diamines with high enantioselectivities and good to high yields. This powerful and efficient reaction is achieved by rational design and engineering of chiral diborons, which participate in a [3,3]-sigmatropic rearrangement. DFT studies reveal that different conformational assembling strategies of chiral diborons ensure the excellent enantioselectivity in the tight concerted transition states.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Nanoscience & Nanotechnology
Chen Yang, Weilin Hu, Xuefeng Guo
Summary: Chirality plays a crucial role in various processes and there is a need for accurate distinction among different chiralities. The article proposes a universal strategy for chirality detection and control by aligning the molecular frame with external stimuli.
NANO-MICRO LETTERS
(2023)
Review
Chemistry, Multidisciplinary
Yichen Wu, Peng Wang
Summary: Optically active organosilanes have been demonstrated to be versatile chiral reagents in synthetic chemistry. Monohydrosilanes, which bear a Si-H bond, are especially unique due to their facile transformations through stereospecific bond-formation reactions. In addition, they have also been used as chiral reagents for alcohol resolution, chiral auxiliaries, mechanistic probes, and potential optoelectronic materials.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Chemistry, Multidisciplinary
Masahiro Kawada, Ryo Tsuyusaki, Kosuke Nakashima, Misaki Yamada, Akihiro Kozakai, Yasuyuki Matsushima, Shin-ichi Hirashima, Tsuyoshi Miura
Summary: This study presents the first successful example of asymmetric 1,2-additions of nitromethane to trifluoromethyl enones, and achieved highly functionalized products with high yields and excellent enantioselectivities through a novel N,N-dibenzyl diaminomethylenemalononitrile organocatalyst.
CHEMISTRY-AN ASIAN JOURNAL
(2022)
Article
Chemistry, Multidisciplinary
Jan-Dirk Spoering, Jan Wiesenthal, Victoria S. Pfennig, Jochem Gaetgens, Kassem Beydoun, Carsten Bolm, Juergen Klankermayer, Doerte Rother
Summary: This study demonstrates that a complete chemoenzymatic cascade to form dioxolanes can be carried out in a purely organic environment. The highly stereoselective synthesis of the product was achieved through a two-step enzyme cascade and a ruthenium molecular catalyst.
Article
Chemistry, Physical
Zeng Gao, Chao-Xian Yan, Jinlong Qian, Huameng Yang, Panpan Zhou, Jinlong Zhang, Gaoxi Jiang
Summary: An efficient and rapid method for constructing a family of axially chiral sulfonamides with a wide functional group tolerance has been developed through Pd-catalyzed atroposelective hydroamination. Simple oxidation and gamma-addition enabled the synthesis of various valuable axially chiral sulfonamides and anilides, including non-natural amino acid derivatives. Preliminary DFT calculations were used to explain the origin of asymmetric induction.
Article
Chemistry, Applied
Marcia R. R. Renio, Francisco J. P. M. Sousa, Nelia C. T. Tavares, Artur J. M. Valente, M. Elisa da Silva Serra, Dina Murtinho
Summary: The enantioselective Henry reaction is an important carbon-carbon bond forming reaction that requires the use of efficient chiral catalysts. In this study, in situ formed complexes of N-substituted dihydroxypyrrolidines were evaluated as catalysts, showing that the nature of the N-substituent significantly influences the outcome of the reaction. Best results were obtained using a Cu (II) complex of (3S,4S)-N-benzyl-3,4-dihydroxypyrrolidine, with products having er up to 92:8 (R:S).
APPLIED ORGANOMETALLIC CHEMISTRY
(2021)
Article
Chemistry, Multidisciplinary
Koichi Kodama, Kozue Kawasaki, Meng Yi, Kaguya Tsukarnoto, Hiroaki Shitara, Takuji Hirose
CRYSTAL GROWTH & DESIGN
(2019)
Article
Chemistry, Organic
Koichi Kodama, Meng Yi, Hiroaki Shitara, Takuji Hirose
TETRAHEDRON LETTERS
(2020)
Article
Chemistry, Multidisciplinary
Yingying Zhao, Xiangyong Wang, Ryo Kaneyama, Koichi Kodama, Takuji Hirose
Article
Chemistry, Organic
Koichi Kodama, Shohei Yamaguchi, Shigetaka Hayano, Takashi Houkawa, Yoshinori Kitahara, Hiroaki Shitara, Takuji Hirose
Summary: A hexacyclic chiral aromatic hydrocarbon was synthesized by the reaction between indene and cyclopentadiene, and its enantioseparation was achieved through stereoselective complexation with beta-cyclodextrin and recrystallization. This method has been utilized for large-scale production of both pure enantiomers of the compound, which have also been used as chiral dopants in nematic liquid crystals.
Article
Chemistry, Medicinal
Hayato Kanai, Kuniyo Yamada, Koichi Kodama, Yasuhiro Ishida
Summary: Chiral amphiphiles play an important role in controlling the structures and properties of supramolecular assemblies, but their synthesis has been challenging. Researchers have improved the synthesis efficiency of amphiphilic 1,2-amino alcohols (S)-1 and (1S,2S)-2 by developing new synthetic schemes, resulting in higher overall yields and reduced risk of optical isomerization.
Article
Chemistry, Multidisciplinary
Koichi Kodama, Yuki Shimomura, Takuji Hirose
Summary: Enantiomer separation of nitriles and epoxides was achieved through inclusion crystal formation with organic-salt type chiral hosts. The preferential inclusion of nitriles could be switched by changing the achiral carboxylic acid component. Crystallographic analysis revealed that the hydrogen-bonding networks in the inclusion crystals are controlled by the acidity of the phenol group of the acids, leading to chirality switching.
CRYSTAL GROWTH & DESIGN
(2021)
Article
Polymer Science
Jyorthana Rajappa Muralidhar, Koichi Kodama, Takuji Hirose, Yoshihiro Ito, Masuki Kawamoto
Summary: The introduction of a photocleavable coumarin unit into a polythiophene derivative allowed for controlled changes in the chemical and surface properties of the polymer, opening up new possibilities for the fabrication of optoelectronic devices.
Article
Chemistry, Organic
Srinivas Chandrasekaran, Takuji Hirose, Koichi Kodama
Summary: The optical resolution of chlorine-substituted tropic acids (TAs) by diastereomeric salt formation has been demonstrated. Efficient solvent-induced chirality switching was observed in the case of racemic 2-chlorotropic acid, while no chirality switching was achieved for racemic 3-chlorotropic acid and 4-chlorotropic acid. The position of the chlorine substituent plays an important role in the solvent-induced chirality switching effect.
Article
Chemistry, Multidisciplinary
Jyorthana Rajappa Muralidhar, Koichi Kodama, Takuji Hirose, Yoshihiro Ito, Masuki Kawamoto
Summary: A polymer dispersant was developed for SWCNTs, allowing their dispersion in solvents. The surface properties of the composite film change upon light irradiation, leading to a significant increase in electrical conductivity.
Article
Chemistry, Organic
Koichi Kodama, Kazuhisa Maruyama, Takuji Hirose
Summary: Chiral 1,3-aminosquaramides derived from cis-2-benzamidocyclohexanecarboxylic acid were synthesized and used as bifunctional organocatalysts for asymmetric Michael addition reaction. The optimized organocatalyst achieved an enantioselectivity of up to 96% in the reaction of 1,3-diketones and 1,3-ketoesters with β-nitrostyrenes. Plausible transition state was proposed based on previous reports and DFT calculations.
Article
Chemistry, Multidisciplinary
Hayato Kanai, Kuniyo Yamada, Krishnachary Salikolimi, Koichi Kodama, Yasuhiro Ishida
Summary: In this study, a series of photoreactants were developed by introducing various substituents to 2-anthracenecarboxylic acid, showing different reactivities and selectivities depending on the substituents. The performance of a chiral environment composed of an amphiphilic amino alcohol was evaluated, and achieved excellent regio- and enantioselectivities in the photocyclodimerization reaction. Furthermore, the first stereocontrolled cross-photocyclodimerization between two prochiral anthracenes was successfully achieved in the chiral environment.
CHEMISTRY-A EUROPEAN JOURNAL
(2022)
Article
Chemistry, Multidisciplinary
Koichi Kodama, Masato Obata, Sho Sugimura, Hiroki Yuhara, Takuji Hirose
Summary: This study describes the formation of low-molecular-weight gelators derived from chiral cyclic beta-amino acids. The influence of their stereochemistry on the gelation of organic solvents was investigated, and the intermolecular interactions in the xerogels were analyzed using various spectroscopic and microscopic techniques. The alkyl chain length of the gelators was also examined, and their potential for chiral recognition of amines was demonstrated.
CHEMISTRY-A EUROPEAN JOURNAL
(2023)
Article
Biochemistry & Molecular Biology
Srinivas Chandrasekaran, Masaki Tambo, Yuta Yamazaki, Tatsuro Muramatsu, Yusuke Kanda, Takuji Hirose, Koichi Kodama
Summary: Enantioseparation of 3-hydroxycarboxylic acids was achieved by forming diastereomeric salts using 2-amino-1,2-diphenylethanol and cinchonidine as resolving agents. The resolving agents efficiently separated racemic forms of 3-hydroxy-4-phenylbutanoic acid, 3-hydroxy-4-(4-chlorophenyl)butanoic acid, and 3-hydroxy-5-phenylpentanoic acid. Crystallizing the less-soluble diastereomeric salt of 1 and cinchonidine using ethanol produced a high yield of pure (R)-1·cinchonidine salt. The crystal structures of the less-soluble diastereomeric salts revealed the importance of hydrogen bonding and CH/pi interactions in reinforcing their structures.
Article
Chemistry, Multidisciplinary
Koichi Kodama, Fusato Takase, Takuji Hirose
Summary: Amidine-based optically active resolving agents have been developed for enantiomer separation of axially chiral 1,1'-biaryl-2,2'-diols. A strongly basic amidine forms diastereomeric salts with weakly acidic phenol derivatives, allowing for high yields of enantiopure products. X-ray crystallography reveals that the amidine moiety interacts with the phenol group through salt formation, aided by additional intermolecular NH/pi interactions.
Article
Chemistry, Multidisciplinary
Koichi Kodama, Ryuta Kawamata, Takuji Hirose
NEW JOURNAL OF CHEMISTRY
(2019)
