Copper-Catalyzed Asymmetric Hydrogenation of Aryl and Heteroaryl Ketones
作者:Scott W. Krabbe、Mark A. Hatcher、Roy K. Bowman、Mark B. Mitchell、Michael S. McClure、Jeffrey S. Johnson
DOI:10.1021/ol4021223
日期:2013.9.6
High throughput screening enabled the development of a Cu-based catalyst system for the asymmetric hydrogenation of prochiral aryl and heteroarylketones that operates at H2 pressures as low as 5 bar. A ligand combination of (R,S)-N-Me-3,5-xylyl-BoPhoz and tris(3,5-xylyl)phosphine provided benzylic alcohols in good yields and enantioselectivities. The electronic and steric characteristics of the ancillary
Retracted: The Manganese(I)‐Catalyzed Asymmetric Transfer Hydrogenation of Ketones: Disclosing the Macrocylic Privilege
作者:Alessandro Passera、Antonio Mezzetti
DOI:10.1002/anie.201912605
日期:2020.1.2
The bis(carbonyl) manganese(I) complex [Mn(CO)2 (1)]Br (2) with a chiral (NH)2 P2 macrocyclic ligand (1) catalyzes the asymmetrictransferhydrogenation of polar double bonds with 2-propanol as the hydrogen source. Ketones (43 substrates) are reduced to alcohols in high yields (up to >99 %) and with excellent enantioselectivities (90-99 % ee). A stereochemical model based on attractive CH-π interactions
A series of Mn(I) catalysts containing imidazole-based chiral PNN tridentateligands with controllable ‘side arm’ groups have been established, enabling the inexpensive base-promoted asymmetric hydrogenation of simple ketones with outstanding activities (up to 8200 TON) and good enantioselectivities (up to 88.5% ee). This protocol features wide substrate scope and functional group tolerance, thereby
Iridium-Catalyzed Asymmetric Hydrogenation of Ketones with Accessible and Modular Ferrocene-Based Amino-phosphine Acid (f-Ampha) Ligands
作者:Jianfei Yu、Jiao Long、Yuhong Yang、Weilong Wu、Peng Xue、Lung Wa Chung、Xiu-Qin Dong、Xumu Zhang
DOI:10.1021/acs.orglett.6b03862
日期:2017.2.3
A series of tridentate ferrocene-based amino-phosphine acid (f-Ampha) ligands have been successfully developed. The f-Ampha ligands are extremely air stable and exhibited excellent performance in the Ir-catalyzed asymmetric hydrogenation of ketones (full conversions, up to >99% ee, and 500 000 TON). DFT calculations were performed to elucidate the reaction mechanism and the importance of the −COOH
Generation of Axially Chiral Fluoroallenes through a Copper-Catalyzed Enantioselective β-Fluoride Elimination
作者:Thomas J. O’Connor、Binh Khanh Mai、Jordan Nafie、Peng Liu、F. Dean Toste
DOI:10.1021/jacs.1c05769
日期:2021.9.1
difluorides to generate axiallychiral, tetrasubstituted monofluoroallenes in both good yields (27 examples >80%) and enantioselectivities (82–98% ee). Compared to previously reported synthetic routes to axiallychiralallenes (ACAs) from prochiral substrates, a mechanistically distinct reaction has been developed: the enantiodiscrimination between enantiotopic fluorides to set an axial stereocenter. DFT