Chiral Pincer Ruthenium and Osmium Complexes for the Fast and Efficient Hydrogen Transfer Reduction of Ketones
作者:Walter Baratta、Fabio Benedetti、Alessandro Del Zotto、Lidia Fanfoni、Fulvia Felluga、Santo Magnolia、Elisabetta Putignano、Pierluigi Rigo
DOI:10.1021/om1004918
日期:2010.8.23
were found to efficiently catalyze the asymmetric transfer hydrogenation of acetophenone in 2-propanol at 60 °C and in the presence of NaOiPr. On the basis of these data, the 2-naphthyl ruthenium and osmium derivatives [RuCl(CNN)((R,S)-Josiphos*)] (8) (HCNN = (S)-1g) and [OsCl(CNN)(PP)] (PP = (R,S)-Josiphos, 9, and (R,S)-Josiphos*, 10) were isolated from [MCl2(PPh3)3], (R,S)-Josiphos diphosphines, and
一系列手性HCNN配体((S)-1b - g)(S)-2-(1-氨乙基)-6-(芳基)吡啶(芳基= 4-MeO-苯基,1b ; 4-CF 3-苯基,1c; 3,5-二-Me-苯基,1d; 3,5-二-CF 3-苯基,1e; 1-萘基,1f; 2-萘基,1g)从商业2-乙酰基-6开始合成-溴吡啶(2),通过化学酶法涉及相应仲醇(rac - 3)的动态动力学拆分。所得的(R)-的转换3,以98%ee的产率制得,进入同手性胺((S)-6)中,然后与适当的芳基硼酸7b - g进行Suzuki偶联,获得了以97%ee分离的(S)-1b - g总收率可达50%。由[MCl 2(PPh 3)3 ],(R,S)-Josiphos diphosphines和[MCl(CNN)(PP)](M = Ru,Os; PP = Josiphos diphosphine)原位生成的钳形复合物配体(S)-1b - g发现在NaO