The Photochemistry of <i>trans</i>-<i>o</i><i>rtho</i>-, <i>-m</i><i>eta</i>-, and -<i>p</i><i>ara</i>-Aminostilbenes
作者:Frederick D. Lewis、Rajdeep S. Kalgutkar、Jye-Shane Yang
DOI:10.1021/ja992335q
日期:1999.12.1
para isomer is larger than that of the ortho or meta isomer. The para isomer has a short singlet lifetime and high photoisomerization quantum yield, similar to those for trans-stilbene. In contrast, the ortho and meta isomers have long singlet lifetimes and low photoisomerization quantum yields. Isomerization of the para isomer is a singlet-state process, whereas isomerization of both the ortho and
报道了反式氨基二苯乙烯的三种位置异构体的光化学行为,并与未取代的反式二苯乙烯的光化学行为进行了比较。对位异构体的吸收光谱显示出单一的强长波长带;然而,由于构型相互作用,间位和邻位异构体显示出两个强度较低的谱带。所有三种异构体都是荧光的,并且它们的荧光最大值显示出类似的溶剂引起的位移。对位异构体的荧光速率常数大于邻位或间位异构体的荧光速率常数。对位异构体具有短的单线态寿命和高的光异构化量子产率,类似于反式二苯乙烯。相比之下,邻位异构体和间位异构体的单线态寿命长,光异构化量子产率低。对位异构体的异构化是一个单线态过程,而邻位异构体和间位异构体的异构化是一个三重态过程。正交和元的单线态扭转势垒的下限...