Article
Chemistry, Inorganic & Nuclear
Raill R. Quinonez-Lopez, Sara A. Cortes-Llamas, J. Roberto Estrada-Flores, Jose G. Alvarado- Rodriguez, Oscar Blanco-Alonso, A. Aaron Peregrina-Lucano, Elvia Becerra-Martinez, I. Idalia Rangel-Salas
Summary: Heteroleptic [RhIIICp*(NHC)] and [IrIIICp*(NHC)] complexes with a N-amino acid functionality derived from imidazolium salts were synthesized and characterized. The structure of [RhCp*{kappa 2(C,O)-NHC}Cl] complex 3f was discussed as a pair of diastereomers. The catalysts showed good yields for the transfer hydrogenation of ketones in basic propan-2-ol, and a chromatographic method for measuring compounds in the reaction was validated. These Rh and Ir complexes provide a new approach in developing catalysts based on classical NHC precursors.
Article
Chemistry, Multidisciplinary
Lu Qian, Xixia Tang, Yulei Wang, Guixia Liu, Zheng Huang
Summary: The use of a chiral (NCP)Ir complex as the precatalyst allows for the asymmetric transfer hydrogenation of diaryl ketones. This method is applicable to various ortho-substituted diaryl ketones and can be conducted in gram scale under mild reaction conditions.
CHINESE JOURNAL OF CHEMISTRY
(2022)
Article
Chemistry, Physical
Jitao Yang, Lijun Yao, Zheng Wang, Zheng Zuo, Siyuan Liu, Pengxiang Gao, Mingyang Han, Qingbin Liu, Gregory A. Solan, Wen-Hua Sun
Summary: A new chiral ligand, LPNN-1, was successfully used in Mn-catalyzed asymmetric transfer hydrogenation and asymmetric hydrogenation. The Mn-pincer complex Mn-1 showed better catalytic performance, leading to higher enantioselectivities. DFT calculations and experimental investigations proposed a possible mechanism for the Mn-catalyzed ATH.
JOURNAL OF CATALYSIS
(2023)
Article
Chemistry, Inorganic & Nuclear
Miguel Gonzalez-Lainez, M. Victoria Jimenez, Vincenzo Passarelli, Jesus J. Perez-Torrente
Summary: Neutral and cationic cyclooctadiene rhodium(i) complexes with a lutidine-derived polydentate ligand have been synthesized and found to efficiently catalyze the hydrosilylation of 1-hexyne with high selectivity. These catalysts exhibit a different β-(Z) selectivity compared to previously reported rhodium(i) catalysts based on 2-picolyl-functionalized NHC ligands. Kinetic studies suggest an energy barrier of 19.8±2.0 kcal mol(-1) for the hydrosilylation reaction.
DALTON TRANSACTIONS
(2023)
Article
Chemistry, Organic
Jia-Yin Wang, Guigen Li, Wen-Juan Hao, Bo Jiang
Summary: A new asymmetric catalytic conjugate reduction method has been established for synthesizing enantioenriched cyclobuta[a]-naphthalen-4(2H)-ones using copper-bisphosphine complexes as catalysts, providing excellent regio- and enantioselectivities. This protocol is tolerant to a broad scope of substrates, exhibits high compatibility with various substituents, and offers excellent stereoselectivity.
Article
Chemistry, Inorganic & Nuclear
Roman I. Nekrasov, Tat'yana A. Peganova, Ivan V. Fedyanin, Evgenii I. Gutsul, Oleg A. Filippov, Natalia V. Belkova, Alexander M. Kalsin
Summary: A series of pentamethylcyclopentadienyl rhodium complexes were synthesized and characterized, and some complexes were found to have low stability and high nucleophilicity and reactivity.
INORGANIC CHEMISTRY
(2022)
Article
Multidisciplinary Sciences
Congcong Yin, Ya-Fei Jiang, Fanping Huang, Cong-Qiao Xu, Yingmin Pan, Shuang Gao, Gen-Qiang Chen, Xiaobing Ding, Shao-Tao Bai, Qiwei Lang, Jun Li, Xumu Zhang
Summary: In this paper, an efficient anionic Ir catalyst for asymmetric hydrogenation of ketones is reported, which exhibits biocatalysis-like efficacy with high enantiomeric excess and turnover number. In industrial applications, this catalyst plays a significant role in a highly selective process route.
NATURE COMMUNICATIONS
(2023)
Article
Chemistry, Organic
Irena Dokli, Antonija Ozegovic, Aleksandra Simanovic, Matija Hromin, Anamarija Knezevic, Aleksandar Visnjevac, Andreja Lesac
Summary: Chiral liquid crystals (LCs) are promising functional soft materials with unique optical and mechanical properties. In this study, a versatile chiral 3-aryl-3-hydroxypropanoic ester moiety was introduced as a building block for LC compound preparation. Chiral LC compounds with diverse topologies were successfully synthesized, and their mesomorphic behavior was consistent with their topology. The study also identified different liquid crystal phases, demonstrating the self-organization and structure-property relationship in chiral LCs.
JOURNAL OF ORGANIC CHEMISTRY
(2022)
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)
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
Chemistry, Multidisciplinary
Tianjiao Hu, Lukas Lueckemeier, Constantin Daniliuc, Frank Glorius
Summary: The direct enantioselective hydrogenation of 2-quinolones using Ru(II)-NHC catalyst has been achieved, providing alkyl-, aryl- and halogen-substituted optically active dihydro-2-quinolones in high yields with moderate to excellent enantioselectivities. This reaction presents an efficient and atom-economic pathway to construct simple chiral 3,4-dihydro-2-quinolones.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2021)
Article
Chemistry, Multidisciplinary
Juana M. Perez, Roxana Postolache, Marta Castineira Reis, Esther G. Sinnema, Denisa Vargova, Folkert de Vries, Edwin Otten, Luo Ge, Syuzanna R. Harutyunyan
Summary: Chiral Mn(I) complexes have been shown to activate H-P bonds, providing a general method for the hydrophosphination of internal and terminal alpha,beta-unsaturated nitriles. Metal-ligand cooperation, a previously unconsidered strategy for catalytic H-P bond activation, plays a key role in the mechanistic action of the Mn(I)-based catalyst. Computational studies support a stepwise mechanism for the hydrophosphination reaction and offer insights into the origin of enantioselectivity.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2021)
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, Physical
Xue-Song Gu, Ying Xiong, Fan Yang, Na Yu, Pu-Cha Yan, Jian-Hua Xie, Qi-Lin Zhou
Summary: An iridium-catalyzed asymmetric hydrogenation method involving dynamic kinetic resolution was successfully developed using chiral spiro PNN-ligands containing a C5-substituted chiral oxazoline unit. This protocol, combined with simple dehydration, provides a straightforward approach to prepare enantiomerically enriched 3-aryloxy tetrahydrofurans, which are prevalent structural motifs in many approved drugs and clinical candidates.
Article
Chemistry, Organic
Danielle L. J. Pinheiro, Martin Nielsen
Summary: The chemoselective reduction of enamides to alpha-amino acids using Ru pincer complexes as catalysts and iPrOH and EtOH as H-donors and solvents is demonstrated. A range of alpha-amino acids is synthesized with good to excellent yields. Applications, large-scale synthesis, and a one-pot experiment are also reported. Deuterium-labeling experiments show high regioselectivity between the alpha- and beta-positions of the alkene unit.
JOURNAL OF ORGANIC CHEMISTRY
(2022)