examples of atropisomerically stable diarylamines in the literature, as the contiguous axes can allow for low energy racemization pathways via concerted bond rotations. Herein, we describe highly atropisomerically stable diarylamines that possess barriers to racemization of 30–36 kcal/mol, corresponding to half-lives to racemization on the decade to century time scale at room temperature. Investigation
二芳基胺具有两个潜在的阻转异构 C-N 轴;然而,文献中很少有阻转异构稳定的二芳基胺的例子,因为相邻的轴可以通过协调的键旋转实现低能量外消旋化途径。在此,我们描述了高度阻转异构稳定的二芳基胺,它们具有 30-36 kcal/mol 的消旋化屏障,对应于室温下十年到世纪时间尺度的消旋化半衰期。对导致高立体
化学稳定性的因素的研究表明,
苯胺孤电子对与更缺乏电子的芳环的共轭增加,再加上分子内氢键,将相应的轴锁定为确定的平面构象,不利于较低能量的消旋途径。