Article
Chemistry, Multidisciplinary
Yunnan Xu, Delong Liu, Yu Deng, Yi Zhou, Wanbin Zhang
Summary: An asymmetric hydrogenation of 3-benzoylaminocoumarins was achieved for the first time using the BridgePhos-Rh catalytic system, providing chiral 3-amino dihydrocoumarins in high yields and with excellent enantioselectivities. The relationship between the enantioselectivities of the hydrogenations and the dihedral angles and the resulting pi-pi stacking effects of the BridgePhos-Rh complexes, determined by X-ray diffraction analysis, was discussed. The corresponding hydrogenated products allow for many transformations, providing several chiral skeletons with important physiological and pharmacological activities.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2021)
Article
Chemistry, Organic
Yu Nie, Qianjia Yuan, Feng Gao, Masahiro Terada, Wanbin Zhang
Summary: An efficient iridium-catalyzed double asymmetric hydrogenation of 2,5-dialkylienecyclopentanones is reported, delivering chiral 2,5-disubstituted cyclopentanones in excellent yields and stereoselectivities. The results suggest that the two C=C bonds were hydrogenated in a stepwise manner and the second stereocenter was controlled by the chiral catalyst and the chirality of monohydrogenated product. The hydrogenated products can be prepared on a gram-scale and are easily derivatized.
Article
Chemistry, Organic
Yu Nie, Qianjia Yuan, Feng Gao, Masahiro Terada, Wanbin Zhang
Summary: Herein, we report an efficient iridium-catalyzed double asymmetric hydrogenation of 2,5-dialkylienecyclopentanones, delivering the chiral 2,5-disubstituted cyclopentanones in excellent yields and stereoselectivities. The results of the kinetic experiments and control experiments indicated that the two C=C bonds were hydrogenated in a stepwise manner and the second stereocenter was synergistically controlled by the chiral catalyst and the chirality of monohydrogenated product. The hydrogenated products can be prepared on a gram-scale and are easily derivatized.
Review
Chemistry, Organic
Anirban Sen, Samir H. Chikkali
Summary: This article assesses the potential use of C-1-symmetric diphosphorus ligands in producing chiral compounds through asymmetric hydrogenation, summarizing recent strategies and advancements in metal-catalyzed asymmetric hydrogenation using these ligands. It discusses the potential of diphosphorus ligands in producing pharmaceutical intermediates, bioactive molecules, drug molecules, agrochemicals, and fragrances.
ORGANIC & BIOMOLECULAR CHEMISTRY
(2021)
Article
Chemistry, Organic
Yi-Fan Wang, Yu-Han He, Yan Su, Yang Ji, Rui Li
Summary: In this study, a palladium complex coordinated with a chiral SIPHOS ligand was evaluated as an efficient catalyst for asymmetric hydrosilylation reaction. The results showed that good to excellent enantioselectivities could be obtained in the hydrosilylation reaction of 1-aryl-2-silyl ethanols with selectively converted trichlorosilyl groups. Additionally, stable and high-yielding 1,2-bis(silyl) chiral compounds could be produced through the asymmetric hydrosilylation of beta-silyl styrenes followed by methylation of the trichlorosilyl group.
JOURNAL OF ORGANIC CHEMISTRY
(2022)
Article
Chemistry, Multidisciplinary
Guillaume Force, Robert J. J. Mayer, Marie Vayer, David Leboeuf
Summary: Chiral naphthalene diimide ligands (NDIPhos) were utilized in rhodium-catalyzed enantioselective hydrogenation, where these ligands' key feature is their self-assembly ability through pi-pi interactions to mimic bidentate ligands, offering an alternative to traditional supramolecular strategies. This concept was further supported by calculations using the composite electronic structure method r(2)SCAN-3c.
CHEMICAL COMMUNICATIONS
(2023)
Article
Chemistry, Organic
Chao Dong, Dao-Sheng Liu, Lei Zhang, Xiang-Ping Hu
Summary: An enantioselective Rh-catalyzed hydrogenation of E/Z mixtures of trisubstituted vinyl esters has been achieved using a chiral ferrocenylphosphine-phosphoramidite ligand. The reaction showed high yields and good to high enantioselectivities, with the presence of a small amount of t-butanol benefiting the hydrogenation outcome.
TETRAHEDRON LETTERS
(2021)
Review
Chemistry, Organic
Li Xin, Song Qiuling
Summary: Chiral boranes have emerged as privileged catalysts in asymmetric reactions due to their lower catalyst loading and easier access compared to chiral transition metal catalysts. This article summarizes and discusses the chiral borane-catalyzed enantioselective reactions, organized into three parts based on reaction categories.
CHINESE JOURNAL OF ORGANIC CHEMISTRY
(2022)
Article
Chemistry, Physical
Liexin Wu, Huiying Xu, Hui Gao, Liping Li, Weijie Chen, Zhi Zhou, Wei Yi
Summary: The study presents a (CpRh)-Rh-X(III)-catalyzed enantioselective intermolecular carboamination of 1,3-dienes, allowing the direct synthesis of chiral allylic amines with phenol functionalities under mild conditions. The mechanistic pathway involves an unusual Rh(III)-Rh(I)-Rh(III) catalytic cycle and has shown potential in the derivation of natural products and bioactive complexes.
Review
Chemistry, Multidisciplinary
Heng Wang, Jialin Wen, Xumu Zhang
Summary: Asymmetric hydrogenation of double bonds is an effective method for preparing chiral molecules, with noble metals and bidentate ligands showing remarkable reactivity. The development of chiral tridentate ligands has become increasingly important, enabling both reactivities and stereoselectivities in asymmetric hydrogenation. While noble metal catalysts with chiral tridentate ligands have made significant achievements, there is still a high demand for designing chiral tridentate ligands for earth abundant metal catalysts.
Article
Multidisciplinary Sciences
Jie Wang, Wei-Feng Zheng, Xue Zhang, Hui Qian, Shengming Ma
Summary: This study reports the synthesis of non-readily available enantioenriched tetrasubstituted allenes through rhodium-catalyzed reactions controlled by steric hindrance. Detailed mechanistic experiments and density functional theory studies reveal the mechanism behind the formation of different stereochemistry under different reaction conditions. A stereodivergent protocol to construct the enantiomer of optically active tetrasubstituted allenes from the same starting materials is successfully developed based on these mechanistic understandings.
NATURE COMMUNICATIONS
(2023)
Article
Chemistry, Organic
Xiaolei Ji, Chaoren Shen, Xinxin Tian, Kaiwu Dong
Summary: A palladium-catalyzed asymmetric hydroesterification reaction was developed for preparing chiral alpha-substituted succinates with moderate yields and high ee values. The kinetic profile of the reaction progress indicated that the alkene substrate underwent hydroesterification followed by esterification with alcohol. The enantioselectivity was elucidated by density functional theory computation.
Article
Chemistry, Multidisciplinary
Shuaizhong Zhang, Jinquan Zhang, Hongbin Zou
Summary: Rh-catalyzed selective C-H functionalization of indoles was achieved using two different routes: alkenylation-annulation with the addition of KHSO4 and alkenylation-elimination in the presence of CsOAc. Notably, one-pot hydrolysis and benzoylation of the annulation products yielded easily separable beta-(1H-indol-2-yl)-beta-amino acid derivatives.
CHEMICAL COMMUNICATIONS
(2023)
Article
Chemistry, Organic
Changming Xu, Yinsheng Qi, Xinshuang Yang, Xiangfan Li, Zhenpeng Li, Lei Bai
Summary: A class of C2-symmetric chiral spirocyclic phase-transfer catalysts based on the tetramethyl-1,1'-spirobiindane scaffold was synthesized in 12 steps from commercially available bisphenol A with total yields between 22-25%, featuring a more rigid and stable backbone and smaller dihedral angles that can be easily modified. These catalysts exhibit high catalytic performance in the asymmetric alkylation of tert-butyl glycinate Schiff base at only 2 mol % loading, resulting in target products with yields of up to 92% and 98% ee.
Article
Chemistry, Organic
You-Dong Shao, Jin-Shuo Feng, Dan-Dan Han, Kang-Hui Pan, Ling Zhang, Yi-Fan Wang, Zhong-Hui Ma, Pei-Ru Wang, Mingjing Yin, Dao-Juan Cheng
Summary: The first enantioselective synthesis of axially chiral styrene-type allylamines was achieved through chiral phosphoric acid mediated atroposelective reductive amination of 1-enal substituted 2-naphthols. This protocol features a broad substrate scope, good enantioselectivities (up to 90% ee) and mild reaction conditions, providing a new entry to the challenging atropisomeric acyclic styrene scaffolds.
ORGANIC CHEMISTRY FRONTIERS
(2022)
