Asymmetric Hydrogenation of β-Keto Sulfonamides and β-Keto Sulfones with a Chiral Cationic Ruthenium Diamine Catalyst
Xiao-Fei Huang, Shao-Yun Zhang, Zhi-Cong Geng, Chun-Yuen Kwok, Peng Liu, Hai-Yan Li, and Xing-Wang Wang* (王兴旺)
Key Laboratory of Organic Synthesis of Jiangsu Province, College of Chemistry, Chemical Engineering and Materials Science, Soochow University, Suzhou 215123, People's Republic of China
Adv. Synth. Catal. 2013, 355, 2860-2828.
Abstract: Optically active β-hydroxysulfonamides and β-hydroxysulfones are very important building blocks for the preparation of bioactive compounds and pharmaceuticals. In this work, a highly efficient asymmetric hydrogenation of β-ketosulfonamides and β-ketosulfones has been developed using a phosphine-free chiral Ru(OTf)(TsDPEN)(η6-p-cymene) complex as the catalyst, to afford the corresponding β-hydroxysulfonamides and β-hydroxysulfones in high yields with excellent optical purities. In addition, a cascade asymmetric hydrogenation/dynamic kinetic resolution (DKR) of racemic cyclic β-ketosulfonamides and β-ketosulfones was also realized using the same catalyst, to give the corresponding chiral cyclic β-hydroxysulfonamides and β-hydroxysulfones in good yields with excellent enantio- and diastereo-selectivities.
链接：http://onlinelibrary.wiley.com/doi/10.1002/adsc.201300331/abstract