Rotational isomerism involving an acetylenic carbon. Part 5: Restricted rotation about acetylenic axis in sterically crowded bis(1-phenyl-9-anthryl)ethynes
作者:Shinji Toyota、Toshiaki Makino
DOI:10.1016/j.tetlet.2003.08.079
日期:2003.10
di-9-anthrylethyne derivative with 3,5-iPr2-phenyl groups at 1-position showed a barrier to rotation about the acetylenic axis of 18.0 kcal mol−1 based on a dynamic NMR study, which is an extremely high value for acyclic diarylethynes. The mechanism of the dynamic stereochemistry and the substituent effect on the rotational barrier are discussed.
根据动态NMR研究,标题为在1位具有3,5- i Pr 2-苯基的空间拥挤的di-9-蒽乙炔衍生物显示出绕炔键轴旋转的障碍为18.0 kcal mol -1。无环二芳基乙炔具有极高的价值。讨论了动态立体化学的机理以及取代基对旋转势垒的影响。