Asymmetric synthesis of axially chiral benzamides and anilides by enantiotopic lithiation of prochiral arene chromium complexes
Asymmetric synthesis of axially chiral benzamides and anilides by enantiotopic lithiation of prochiral arene chromium complexes
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DOI：
10.1021/jo011052p
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发表时间：
2002-03-22
影响因子：
3.6
通讯作者：
Uemura, M
中科院分区：
文献类型：
--
作者：
Koide, H;Hata, T;Uemura, M
N，N-二乙基2，6-二甲基苯甲酰胺(1)和N-甲基-N-酰基2，6-二甲基苯胺(14和21)的前手性三羰基铬(1)与手性锂盐碱形成的前手性三羰基铬(1)和N-甲基-N-酰基2，6-二甲基苯胺(14和21)通过对映体对映异构化反应和亲电取代反应合成了手性苯甲酰胺和苯胺类化合物，产率高，光学纯度高。得到的轴向手性铬络合苯甲酰胺和苯胺在空气中被氧化，得到无铬的轴向手性苯甲酰胺和苯胺类对映体，在室温下没有轴向键旋转。
Axially chiral benzamides and anilides were prepared by enantiotopic lithiation at the distinguished benzylic methyl of prochiral tricarbonylchromium complexes of N,N-diethyl 2,6-dimethylbenzamide (1) and N-methyl-N-acyl 2,6-dimethylaniline (14 and 21) with a chiral lithium amide base followed by electrophilic substitution in good yields with high optical purity. The resulting axially chiral chromium-complexed benzamides and anilides were oxidized under air to give chromium-free axially chiral benzamides and anilides in an enantiomerically active form without axial bond rotation at room temperature.