Enantioselective Hydrogenation of Diarylmethanimines for Synthesis of Chiral Diarylmethylamines
作者:Duanyang Kong、Meina Li、Guofu Zi、Guohua Hou、Yong He
DOI:10.1021/acs.joc.6b01273
日期:2016.8.5
An enantioselectivehydrogenation of N-substituted diarylmethanimines under mild conditions has been first realized by using an iridiumcatalyst with a chiral f-spiroPhos ligand. This method provides an efficientaccess to the asymmetric synthesis of a variety of chiral diarylmethylamines and their derivatives with excellent enantioselectivities (up to 99.4% ee) and high turnover numbers (TON up to
2‐bis(di‐tert‐butylphosphinoxy)ethane (tBu2POCH2CH2OPtBu2) was synthesized. In the presence of this ligand, various N‐acyl enamides were obtained in good yields and chemoselectivity by Pd‐catalyzed carbonylation reaction of imines containing α‐H. Meanwhile, imines without α‐H could be transformed to N‐acyl imines, which form highly hindered amides by straightforward addition of Grignard reagents.
首次合成了二齿次膦酸酯配体1,2-双(二叔丁基次膦氧基)乙烷(t Bu 2 POCH 2 CH 2 OP t Bu 2)。在存在这种配体的情况下,通过Pd催化含α-H的亚胺的羰基化反应,可以得到高收率和化学选择性的各种N-酰基酰胺。同时,不含α-H的亚胺可以转化为N-酰基亚胺,通过直接添加格利雅试剂即可形成受阻酰胺。