Review
Chemistry, Multidisciplinary
Dian-Feng Chen, Liu-Zhu Gong
Summary: This article introduces the fundamental attributes of asymmetric organo/transition-metal combined catalysis (AOMC), explains how organocatalysts and transition-metal complexes collaborate, and discusses future opportunities in this field.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2022)
Article
Chemistry, Physical
Qingqing Luo, Zhou Tian, Jie Tang, Jie Wang, Yin Tian, Cheng Peng, Gu Zhan, Bo Han
Summary: The study focuses on the design of bifunctional 4-pyrrolidinopyridines as Lewis base catalysts, which exhibited excellent efficiency and stereoselectivity in asymmetric cycloaddition reactions. The research provides strong support for the construction of chiral spiropyrazolone derivatives.
Article
Chemistry, Multidisciplinary
Kohei Watanabe, Jia Hao Pang, Ryo Takita, Shunsuke Chiba
Summary: Organomagnesium compounds, like Grignard reagents, are classic and versatile carbanion species prepared through various methods, while organo-alkaline earth metal complexes can be generated from unsaturated molecules and exhibit unique reactivity in downstream functionalization. The latter can further be functionalized with electrophiles, showing exceptional reactivity compared to organomagnesium complexes.
Article
Chemistry, Multidisciplinary
Yuan Gao, Zhijun Wang, Xinyu Zhang, Min Zhao, Shuai Zhang, Chao Wang, Liang Xu, Pengfei Li
Summary: In this study, novel chiral half-sandwich iridium catalysts were designed and synthesized, which enabled the preparation of a broad range of α-chiral (hetero)aryl amines with high yield and enantioselectivity. The optimized catalyst and azeotropic mixture of formic acid and triethylamine were used as the hydrogen source under mild and operationally simple conditions. This work introduced an effective chiral catalyst for the simplified synthesis of medicinally important chiral amines, and also provided a rare example of robust enantioselective transition-metal catalysis.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Organic
Ming-Hui Xu, Yong-Hai Yuan, Dong-Dong Liang, Xiao-Ming Zhang, Fu-Min Zhang, Yong-Qiang Tu, Ai-Jun Ma, Kun Zhang, Jin-Bao Peng
Summary: A novel spiro-pyrrolidine-derived bifunctional thiourea catalyst has been developed for stereoselective conjugate addition of furfurals to beta,gamma-unsaturated alpha-ketoesters. The rigid spirocyclic framework of the catalyst is essential for highly enantioselective transformation in the asymmetric trienamine catalysis of benzylic C-H functionalization of 5-benzylfurfurals.
ORGANIC CHEMISTRY FRONTIERS
(2021)
Article
Chemistry, Multidisciplinary
Jacqueline Bitai, Alastair J. Nimmo, Alexandra M. Z. Slawin, Andrew D. Smith
Summary: A new method for the enantioselective synthesis of substituted vinylcyclopentanes has been developed using cooperative palladium and isothiourea catalysis. Functionalized cyclopentanes can be synthesized with good yields and stereocontrol by intermolecular cycloaddition between reactive intermediates.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Chemistry, Multidisciplinary
Hu Tian, Hong-Ming Zhang, Liang Yin
Summary: In this article, a copper(I)-catalyzed asymmetric conjugate addition/protonation with selenols and alpha-substituted alpha,beta-unsaturated thioamides is described, which produces a series of chiral selenides with high to excellent enantioselectivity. The reaction shows a broad substrate scope for both selenols and alpha-substituted alpha,beta-unsaturated thioamides. The catalytic system is also successfully used for asymmetric selenation of beta-substituted alpha,beta-unsaturated thioamides. A [Cu-(R,R-P)-TANIAPHOS]-SePh species is identified by Se-77 NMR spectra, with a chemical shift at delta 462 ppm. Furthermore, a {[Cu-(R)-TOL-BINAP]-SePh}(2) species is characterized by X-ray analysis, confirming the formation of Cu-Se bond in the reaction. Finally, the straightforward transformations of the thioamide group to amine and thioester are demonstrated.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Multidisciplinary
Yue Zheng, Di Xu, Lei Zhang, Xi Chen
Summary: In this study, glucosaminic acid (GlcNA) was efficiently produced from chitin biomass-derived glucosamine (GlcN) using zinc oxide-supported gold nanoparticles (Au/ZnO) as catalyst. The Au/ZnO catalyst prepared by the deposition-precipitation (DP) method exhibited superior catalytic performance compared with the deposition-reduction (DR) method, resulting in a >2-fold increase in product yield. The average particle size of Au nanoparticles and the surface oxygen vacancy sites were found to be crucial factors affecting the catalytic activity.
CHEMISTRY-AN ASIAN JOURNAL
(2022)
Article
Chemistry, Organic
Singarajanahalli Mundarinti Krishna Reddy, Subramaniyan Prasanna Kumari, Subramaniapillai Selva Ganesan
Summary: The palladium-catalyzed addition of arylboronic acid to 2-cyano-(N-aryl)-acetamide or ethyl-2-cyanoacetate followed by subsequent reaction transforms them into biologically significant derivatives. The reaction conditions are robust enough to prevent hydrolysis of the ester/amide moiety during arylation, and can also convert the unactivated nitrile moiety in acetonitrile to the corresponding acetophenone derivative.
TETRAHEDRON LETTERS
(2021)
Article
Chemistry, Organic
Enbo Yu, Guojiang Mao, Guo-Jun Deng, Fuhong Xiao
Summary: This paper describes a metal-free chemoselective reduction of α,β-unsaturated carbonyl compounds using water as a hydrogen donor. Various functional groups attached to substrates were well tolerated, and the corresponding products were obtained in moderate to good yields under simple reaction conditions. This reaction has great potential to be a general and practical reduction methodology in organic transformation.
ORGANIC CHEMISTRY FRONTIERS
(2023)
Article
Chemistry, Organic
Guangning Ma, Samson Afewerki, Kaiheng Zhang, Ismail Ibrahem, Armando Cordova
Summary: The study demonstrates the ability of intermolecular cooperative thiourea/oxime hydrogen-bond catalysis to improve and accelerate asymmetric aminocatalysis by achieving highly stereoselective transformations through synergy.
EUROPEAN JOURNAL OF ORGANIC CHEMISTRY
(2021)
Article
Chemistry, Multidisciplinary
Ronghua Zhang, Shan Xu, Zhou Luo, Yuanyuan Liu, Junliang Zhang
Summary: Central chirality is an important aspect in the design of chiral ligands and catalysts. This study focuses on the exploration of N-chirality in chiral ligand design, which has been rarely studied before. The authors demonstrate the design, synthesis, and application of a class of P,N-ligands with flexible N-chirality and their derived iridium complexes with fixed N-chiral stereocenters. Computational studies emphasize the importance of N-chirality and the N-H group in the catalytic activity of these complexes.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Organic
Jia-Lu Zhang, Jin-Yu Liu, Guo-Qiang Xu, Yong-Chun Luo, Hong Lu, Chang-Yin Tan, Xiu-Qin Hu, Peng-Fei Xu
Summary: A novel one-pot triple-reaction strategy for the asymmetric construction of polycyclic skeletons with multiple consecutive chiral centers has been reported, resulting in the formation of a wide range of polycyclic tetrahydroquinoline derivatives with good results. This transformation involves the successive formation of five chemical bonds and five consecutive chiral centers.
Article
Chemistry, Organic
Giacomo Pugliese, Francesco Vaghi, Giovanni Lonardi, Giulia Licini, Manuel Orlandi
Summary: Co-Salox complexes are efficient catalysts for reducing prochiral alpha,beta-unsaturated esters. They can be easily prepared from inexpensive materials, offering a viable alternative to previously reported Co-catalysts. The presence of NaBH4 and EtOH in the reaction leads to the stereoselective formation of chiral esters, amides, and nitriles with high yields and enantioselectivities. The reactivity and enantioselectivity are influenced by the concentration of the reductant counter cation (Na+) and the polarity of the solvent, suggesting a complex mechanistic pathway.
EUROPEAN JOURNAL OF ORGANIC CHEMISTRY
(2023)
Article
Chemistry, Multidisciplinary
Zeyuan Wei, Hengxu Li, Yujie Wang, Qiang Liu
Summary: The reactivity of metal-hydride complexes can be controlled by modifying ancillary ligands. In this study, a versatile and efficient NHC-based NNC-pincer Mn catalyst was designed to enhance the hydride-donor ability and reduce steric hindrance. The newly developed catalyst showed higher activity than the corresponding NNP-pincer Mn catalyst, enabling successful hydrogenation of a wide range of polar unsaturated compounds under mild conditions. This work presents a rare example of a general phosphine-free Mn-catalyzed hydrogenation system.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Organic
Fuying Zhu, Yamei Lin
Summary: In this study, a low-metal iron-supported catalyst (Fe20/NC-Mg) was reported for the efficient synthesis of quinoxaline compounds, using water as a solvent and without additional bases. The synergistic effect of FeNx site and Mg (OH)2 nanorods in the catalyst played a key role in achieving high yields (82-91%) in 16 examples. The gram-level synthesis and reusability of the catalysts after four cycles demonstrated its industrial application potential.
Article
Chemistry, Organic
Mikhail Kozlov, Alexey Tyurin, Andrey Dmitrenok, Vyacheslav Rusak, Aleksander Fedorov, Igor Zavarzin, Yulia Volkova
Summary: This study presents a novel and practical synthesis method for phosphorus-substituted 1,3,4-thiadiazolines using phosphorylthioformic acid hydrazides and ketones. The protocol demonstrates operational simplicity, availability of reagents, and tolerance towards different functional groups.
Article
Chemistry, Organic
Jisna Jose, Thomas Mathew
Summary: 2-Cyclopentenone and its derivatives are highly esteemed synthetic intermediates with exceptional utility in organic synthesis. They are favored structural motifs in numerous pharmaceutical drugs and natural products, highlighting their significance. The review discusses the various methods used to synthesize cyclopentenones from 2016 to 2023.