Photochromism of novel chromenes constrained to be part of [2.2]paracyclophane: remarkable ‘phane’ effects on the colored o-quinonoid intermediates
作者:Jarugu Narasimha Moorthy、Susovan Mandal、Amrit Kumar
DOI:10.1039/c2nj40575j
日期:——
The photochemistry of rationally designed chromenes that are constrained to be part of [2.2]paracyclophane, i.e., CP-H and CP-OMe, was investigated to examine the effect of through-space delocalization in the cyclophane core (phane effect) on the photochromic behavior. In contrast to the parent chromene, i.e., 2,2-diphenylbenzopyran CH, for which the photoinduced coloration is not observable at room
合理设计的铬烯的光化学受约束成为其一部分。 [2.2]对环,即,CP-H和CP-OME,进行了调查研究通过空间离域在环芳核(效果PHANE效果)在光致变色特性。与此相反的父烯,即,2,2-二苯基苯并吡喃 CH在室温下无法观察到光致变色,因此,环phan色酮CP-H和CP-OMe使其易于观察到光致变色。负责观察到的颜色的光生邻醌类中间体缓慢还原,从而可以动态监测其衰变。从CP-H和CP-OMe衍生出的光生邻醌类化合物中间体的动力学速率常数的差异证明了明显的贯穿空间的离域化。据我们所知,观察到的结果构成了phane影响的第一个例子。 对反应性中间体的稳定性或其他方面的影响。