8-硝基-1-苯基-3, 3-二甲基吲哚苯骈螺吡喃的光化学

标题螺吡喃(Sp)甲醇溶液直接和二苯酮敏化光发色反应的量子产率分别是0.38和0.53, 2, 3-丁二酮首先猝灭三线态的光发色, 然后, 在较高浓度时, 猝灭单线态的光反应。从敏化和猝灭反应的动力学分析, 计算在直接光解中的初级光物理、光化学过程的量子产率。数据表明, Sp的三线态和单线态都有光反应活性, 这与反应状态相关图分析结果相一致。三线态的参数是3^г=2.2×10^-3ms, k~r=9.13×10^4s^-1, k~d=8.27×10^4s^-1。而且, 一旦生成激发三线态, 它的光化学活性大约比激发单线态大2倍。

Photochemistry of 8'-nitro-1-phenyl-3, 3-dimethylindolinobenzospiropyran

Quantum yields of the photocoloration of the title spiropyran for the direct and benzophenone sensitized photolysis in methanol were 0.38 and 0.53, resp. Biacetyl quenches mainly the triplet photocoloration and to a smaller extent the singlet reaction. From kinetic anal. in the sensitized and quenched reactions, quant. estimation was made of the quantum yields of the primary reactions involved in the direct photolysis. The data suggest that both singlet and triplet of the title spiropyran react to form the colored form. The triplet parameters are as follows: 3t = 2.2 ?10-3 ms; kr = 9.13 ?104 s-1; kd = 8.27 ?104 s-1. Also, the excited triplet state, once populated, is about 2 times more efficient in the formation of the colored form than the excited singlet state.