Article
Chemistry, Physical
Lixian Wang, Jin Lin, Qiangsheng Sun, Chungu Xia, Wei Sun
Summary: A series of Mn(I) catalysts with chiral bidentate benzimidazoles derived from easily available amino acids have been developed for asymmetric transfer hydrogenation (ATH), showing high activity and enantioselectivity. These phosphine-free chiral Mn catalysts can efficiently convert bulky substrates into drug intermediate alcohols, with a possible mechanism and enantiocontrol model proposed based on experimental and DFT studies.
Article
Chemistry, Inorganic & Nuclear
Mustafa Keles, Mustafa Kemal Yilmaz, Simay Ince, Hulya Keles, Hakan Unver
Summary: Chiral P,N,O type imino- and aminophosphine ligands with various substituents were synthesized and tested for their catalytic performance in asymmetric transfer hydrogenation reactions. The isopropyl-substituted chiral aminophosphine ligand in combination with [Ru(cod)Cl-2] was found to be the most efficient catalyst system for the conversion of aromatic ketones with high enantioselectivity.
INORGANICA CHIMICA ACTA
(2021)
Review
Chemistry, Multidisciplinary
Fan Yang, Jian-Hua Xie, Qi-Lin Zhou
Summary: Catalytic asymmetric hydrogenation is a reliable, powerful, and environmentally friendly method for synthesizing chiral molecules. Our recent studies have shown that the design and synthesis of chiral catalysts can greatly improve the efficiency and selectivity of hydrogenation reactions. By adding additional coordinating groups, the stability and efficiency of the catalyst can be significantly increased.
ACCOUNTS OF CHEMICAL RESEARCH
(2023)
Article
Chemistry, Multidisciplinary
Yuki Saito, Shu Kobayashi
Summary: The application of heterogeneous catalysts in continuous-flow enantioselective hydroacylation reactions was studied. Catalysts were prepared by mixing supports and rhodium complexes, and showed excellent activity and enantioselectivity. Under optimized conditions, the catalysts exhibited high turnover numbers and could be applied to various substrates. Furthermore, sequential-flow reactions with other heterogeneous catalysts were demonstrated for the synthesis of biologically active molecules and functional materials.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Inorganic & Nuclear
Zheng Wang, Ning Ma, Xiaochi Lu, Ming Liu, Tian Liu, Qingbin Liu, Gregory A. Solan, Wen-Hua Sun
Summary: A series of manganese(i) carbonyl complexes with structurally related NN- and NNN-chelating ligands were synthesized and used as catalysts for transfer hydrogenation. The NN-systems based on N-R functionalized 5,6,7,8-tetrahydroquinoline-8-amines showed the highest catalytic activity in the conversion of acetophenone to 1-phenylethanol. The N-isopropyl derivative, Mn1, when combined with t-BuONa, achieved efficient reduction of acetophenone and various carbonyl substrates, with high TON values (up to 17,200; TOF of 3550 h(-1)). These findings support an outer-sphere mechanism for the hydrogen transfer and provide a sustainable alternative for producing alcoholic products from carbonyl substrates.
DALTON TRANSACTIONS
(2023)
Article
Chemistry, Inorganic & Nuclear
Mahesh M. Parsutkar, Curtis E. Moore, T. RajanBabu
Summary: This paper presents a practical method for the synthesis and isolation of cobalt(I) bis-phosphine complexes and their use in Co(I)-catalyzed reactions. These complexes exhibit good catalytic activity in low-valent cobalt-catalyzed reactions and can be used in various reactions with sensitive substrates. Additionally, these complexes are useful for synthesizing rare cationic complexes, which show excellent catalytic performance.
DALTON TRANSACTIONS
(2022)
Article
Chemistry, Organic
Zaneta Papadopulu, Martin Oestreich
Summary: A method for the nonenzymatic kinetic resolution of sterically congested alcohols with a quaternary carbon atom in the beta-position is reported, using the catalyst system CuCl/NaOtBu/(R,R)-Ph-BPE together with a 3,5-xylyl-substituted tertiary hydrosilane to achieve enantioselective silylation of the hydroxy group. Several alcohols are obtained with good to excellent selectivity factors, and there are currently no other known straightforward methods to access these motifs.
Article
Chemistry, Multidisciplinary
Guang-Ya Zhang, Sun-Hong Ruan, Yan-Yun Li, Jing-Xing Gao
Summary: The study investigated the asymmetric transfer hydrogenation of a wide range of ketones catalyzed by manganese complex and chiral PxNy-type ligand under mild conditions. By using 2-propanol as a hydrogen source and combining [MnBr(CO)(5)] with chiral, 22-membered macrocyclic ligand (R,R,R',R')-CyP2N4 (L5) with 2% catalyst loading, various ketones could be enantioselectively hydrogenated to afford highly valuable chiral alcohols with up to 95% ee.
CHINESE CHEMICAL LETTERS
(2021)
Article
Chemistry, Physical
Daisuke Sakamoto, Isabel Gay Sanchez, Jiri Rybacek, Jaroslav Vacek, Lucie Bednarova, Marketa Pazderkova, Radek Pohl, Ivana Cisarova, Irena G. Stara, Ivo Stary
Summary: This study describes an asymmetric synthesis method for the preparation of optically pure and conformationally locked oxabenzo[5]helicenes. These compounds can be transformed into cycloiridated organometallics and exhibit excellent catalytic performance in asymmetric transfer hydrogenation reactions.
Article
Chemistry, Multidisciplinary
Tian Du, Biwen Wang, Chao Wang, Jianliang Xiao, Weijun Tang
Summary: A chiral cobalt pincer complex combined with an achiral electron-rich mono-phosphine ligand catalyzes efficient asymmetric hydrogenation of aryl ketones, yielding chiral alcohols with high yields and moderate to excellent enantioselectivities. The achiral mono-phosphine ligand has a remarkable effect on the enantioselectivity of the reaction.
CHINESE CHEMICAL LETTERS
(2021)
Article
Chemistry, Multidisciplinary
Xuefeng Tan, Shuang Gao, Chunyan Yang, Qiwei Lang, Xiaobing Ding, Gen-Qiang Chen, Xumu Zhang
Summary: A series of novel atropisomeric diphosphine ligands termed TanPhos with a smaller bite angle were synthesized and designed. TanPhos exhibited high reactivity and enantioselectivity in the rhodium-catalyzed asymmetric hydrogenation of α-dehydro amino ketones, achieving up to 99% yield and 99% ee for a wide range of chiral α-amino ketones.
SCIENCE CHINA-CHEMISTRY
(2023)
Review
Chemistry, Multidisciplinary
Kingdom Alorku, Chen Shen, Yuhang Li, Ying Xu, Chenguang Wang, Qiying Liu
Summary: The conversion of biomass into platform chemicals, value-added chemicals, or fuels is crucial for sustainability and carbon neutrality. Functionalized metal catalysts are preferred over biological enzymes due to their stability, recyclability, and ease of separation. 2-Methyltetrahydrofuran (MTHF) is an important sugar-derived platform chemical that can be used as a green solvent, fuel additive, or starting material for synthesizing downstream chemicals. This review discusses the challenges and catalytic conversion of biomass to MTHF on precious and non-precious metal-based catalysts, as well as the subsequent conversion of MTHF to value-added downstream chemicals.
Article
Chemistry, Physical
Yunfan Yue, Tian Ma, Hexiang Qi, Yaqi Zhao, Xiaofan Shi, Yanhui Tang, Min Pu, Ming Lei
Summary: In this study, a series of bowl-shaped quadridentate ligands and their manganese catalysts were designed for the hydrogenation of unsaturated bonds using density functional theory. The calculated results suggest that the bowl-shaped structure of the ligands and their connection to the Si-N-Si-C-Si-C six-membered ring core significantly affect the catalytic activity and selectivity. This work provides theoretical insights for designing new transition metal catalysts.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2023)
Article
Chemistry, Physical
Sun-Hong Ruan, Zi-Wei Fan, Wen-Jing Zhang, Han Xu, Dong -Li An, Zan-Bin Wei, Ru-Ming Yuan, Jing-Xing Gao, Yan-Yun Li
Summary: Novel chiral cyclic cobalt(II) complexes were conveniently prepared using readily available CoBr2 and chiral cyclic PxNy-type ligands. Single crystals obtained were used for X-ray diffraction to confirm the structures of these cobalt(II) complexes. The catalytic activity and enantioselectivity of these cobalt(II) complexes in the asymmetric transfer hydrogenation (ATH) of ketones were investigated, and the complex containing chiral macrocyclic iminophosphine ligand CyP2N4 exhibited high efficiency (up to 99% ee).
JOURNAL OF CATALYSIS
(2023)
Article
Chemistry, Applied
Jiayu Zhou, Jianxun Ye, Yang Zhang, Zhaodi Li, Jingjing Li, Delong Liu, Wanbin Zhang
Summary: The RuPHOX-Ru catalyzed asymmetric hydrogenation of diaryl ketones has been developed, yielding chiral diaryl methanols with up to 99% yield and 99% ee. This protocol can be performed on a gram-scale with low catalyst loading (2000 S/C) and the resulting products are valuable for various transformations, especially in the synthesis of chiral drugs like (S)-Orphenadrine and (S)-Neobenodine. Deuterium labeling and control experiments revealed that the RuPHOX-Ru-catalyzed asymmetric hydrogenation is exclusively driven by H-2 as the hydrogen source.
ADVANCED SYNTHESIS & CATALYSIS
(2023)
