New phosphine-amino-alcohol tridentate ligands for ruthenium catalyzed asymmetric transfer hydrogenation of ketones
作者:Orhan Altan、Mustafa Kemal Yılmaz
DOI:10.1016/j.jorganchem.2018.02.046
日期:2018.4
ol tridentateligands (3a-c) and six new rutheniumcomplexes (4a-c and 5a-c) were synthesized and characterized. Catalytic activities of the metal complexes were tested on aryl alkyl ketones. All of the substrates were converted to related sec-alcohols in excellent yields (up to 99%), but enantioselectivities were insufficient (up to 40% ee). Despite the catalytic performance of 5a-c complexes can
Cinchona-Alkaloid-Derived NNP Ligand for Iridium-Catalyzed Asymmetric Hydrogenation of Ketones
作者:Lin Zhang、Ling Zhang、Qian Chen、Linlin Li、Jian Jiang、Hao Sun、Chong Zhao、Yuanyong Yang、Chun Li
DOI:10.1021/acs.orglett.1c04101
日期:2022.1.14
Most ligands applied for asymmetrichydrogenation are synthesized via multistep reactions with expensive chemical reagents. Herein, a series of novel and easily accessed cinchona-alkaloid-based NNP ligands have been developed in two steps. By combining [Ir(COD)Cl]2, 39 ketones including aromatic, heteroaryl, and alkyl ketones have been hydrogenated, all affording valuable chiral alcohols with 96.0–99
大多数用于不对称氢化的配体是通过与昂贵的化学试剂的多步反应合成的。在此,一系列新颖且易于获取的基于金鸡纳生物碱的 NNP 配体已分两步开发。通过结合 [Ir(COD)Cl] 2,包括芳族酮、杂芳基酮和烷基酮在内的 39 种酮被氢化,均能提供有价值的手性醇,其 ee 为 96.0–99.9%。通过NMR、HRMS和DFT讨论了合理的反应机理,并验证了涉及三氢化物的活化模型。