Slow interconversion of enantiomeric conformers or atropisomers of anilide and urea derivatives of 2-substituted anilines
作者:Thomas Adler、Josep Bonjoch、Jonathan Clayden、Mercè Font-Bardía、Mark Pickworth、Xavier Solans、Daniel Solé、Lluís Vallverdú
DOI:10.1039/b507202f
日期:——
N-Acylated 2-substituted anilines undergo slow Ar-N bond rotation, allowing in some cases isolation of enantiomeric or diastereoisomeric atropisomers and in others the determination of the rate of Ar-N bond rotation by NMR. 2-Iodoanilides bearing a branched N-substituent demonstrate sufficient enantiomeric stability to be resolvable, either by HPLC or by formation of diastereoisomeric lactanilide derivatives
N-酰化的2-取代的苯胺经历缓慢的Ar-N键旋转,在某些情况下允许分离对映异构体或非对映异构的阻转异构体,而在其他情况下,可以通过NMR确定Ar-N键的旋转速率。带有支链N-取代基的2-碘代苯胺通过HPLC或通过形成非对映异构的乳酰苯胺衍生物表现出足够的对映体稳定性以可拆分。首次确定了2-取代的N,N'-二芳基脲中Ar-N的旋转速率:它们主要落在50-70 kJ mol(-1)的区域内,对取代基大小的依赖性相对较弱。