作者:Ari Hakgor、Sule Erol Gunal
DOI:10.1016/j.tet.2021.132506
日期:2021.11
Axially chiral 2-thioxo-3-(o-aryl)-quinazolin-4-ones and 2-(benzylthio)-3-(o-aryl)-quinazolin-4-ones were synthesized and their energy barriers to rotation about the N3-Caryl bond were determined by thermal racemization of the separated enantiomers. The rotational barriers were found to range from 112.7 to 140.8 kJ/mol, depending on size of the ortho substituent and to increase linearly with the size
合成了轴向手性 2-thioxo-3-( o - aryl)-quinazolin-4-ones 和 2-(benzylthio)-3-( o -aryl)-quinazolin-4-ones 及其绕 N 旋转的能垒3- C芳基键通过分离的对映异构体的热外消旋化确定。发现旋转势垒范围从 112.7 到 140.8 kJ/mol,这取决于邻位取代基的大小,并且随着邻位卤素取代基的范德华半径的大小线性增加。尽管具有邻位邻位的 N-C 轴向手性化合物的对映体的分离由于氟原子尺寸小,-氟取代基很少见,我们发现带有邻氟基团的喹唑啉-4-酮的旋转势垒足够高,可以分离对映体。