Asymmetric Hydrogenation of γ -Branched Allylamines for the Efficient Synthesis of γ -Chirogenic Amines
Jian Zhang,[a] Yuanhao Wang,[a] Fengfan Zhou,[a]Zhenfeng Zhang,*[a] Ilya D. Gridnev,*[c] and Wanbin Zhang*[a,b]
Abstract: The efficient construction of γ -chirogenic amines has been realized via asymmetric hydrogenation ofγ -branched N -phthaloyl allylamines by using a bisphosphine-Rh catalyst bearing a large bite angle. The desired products possessing different types of γ -substituents were obtained in quantitative yields and with excellent enantioselectivities (up to >99.9% ee). This protocol provided a practical method for the preparation of γ -chirogenic amine derivatives such as the famous antidepressant drug Fluoxetine (up to 50000 S/C). The mechanism calculation shows a weak interaction-promoted activation mode which is completely different from the traditional coordination-promoted activation mode in the Rh-catalyzed hydrogenation.