Evolution of Titanium(IV) Alkoxides and Raney Nickel for Asymmetric Reductive Amination of Prochiral Aliphatic Ketones
作者:Thomas C. Nugent、Vijay N. Wakchaure、Abhijit K. Ghosh、Rashmi R. Mohanty
DOI:10.1021/ol051909v
日期:2005.10.1
[reaction: see text] A new method for the one-pot asymmetric reductive amination of prochiral aliphatic ketones has been developed. The previously unexplored reagent combination of Ti(O(i)Pr)(4)/Raney Ni/H(2) in the presence of (R)- or (S)-alpha-methylbenzylamine provides good to excellent yield (76-90%) and diastereomeric excess (72-98%). The second step, hydrogenolysis, provides the corresponding
[反应:见正文]已经开发了一种用于前手性脂肪族酮的一锅式不对称还原胺化的新方法。Ti(O(i)Pr)(4)/ Raney Ni / H(2)在(R)-或(S)-α-甲基苄胺的存在下未经探索的试剂组合可提供良好至极好的收率(76-90 %)和非对映异构体过量(72-98%)。第二步是氢解,以高收率(88-93%)提供了相应的伯胺,并且毫不妥协的对映体过量。