Arene-iminium salt electron-transfer photochemistry. Mechanistically interesting photoaddition processes
Arene-iminium salt electron-transfer photochemistry. Mechanistically interesting photoaddition processes
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芳烃-亚胺盐电子转移光化学。
DOI：
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发表时间：
1987
期刊：
影响因子：
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通讯作者：
P. Mariano
中科院分区：
文献类型：
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作者：
R. Borg;R. Heuckeroth;A. Lan;S. Quillen;P. Mariano
本文对芳烃-亚胺盐体系的电子转移光化学进行了研究。荧光猝灭研究表明，包括取代甲苯和苯在内的一系列芳烃对2-芳基-1-吡咯啉鎓高氯酸盐的荧光有猝灭作用。在这些情况下，猝灭速率常数与…三角洲G/sub SET/值与可逆电子转移途径淬灭的预期值相同。此外，非共轭亚胺盐猝灭的芳烃与k/子q/值的基础上的电子转移自由能计算的预测平行的主机的荧光。研究了甲苯、苄基三甲基硅烷、苄基三甲基锡烷和2-芳基-1-吡咯啉鎓盐的光加成反应。同样，电子转移诱导的，激发态反应的甲苯和苄基三甲基硅烷与1，2-二甲基-1-吡咯啉鎓高氯酸盐已被研究。这些光反应的结果已被解释的空间位阻，离电基团，和溶剂的影响后，最初形成的自由基阳离子对中间体的竞争途径的速率。最后介绍了苄基三甲基锡烷的光化学。
Studies of the electron-transfer photochemistry of arene-iminium salt systems have been explored. Fluorescence quenching investigations have demonstrated that a series of arenes including substituted toluenes and benzenes quench the fluorescence of a variety of 2-aryl-1-pyrrolinium perchlorates. Quenching rate constants in these cases correlate with the ..delta..G/sub SET/ values as expected for quenching by reversible electron-transfer pathways. In addition, nonconjugated iminium salts quench the fluorescence of a host of arenes with k/sub q/ values which parallel those predicted on the basis of electron-transfer free energy calculations. Photoaddition reactions of toluene, benzyltrimethylsilane, benzyltrimethylstannane, and 2-aryl-1-pyrrolinium salts have been explored. Likewise, electron-transfer-induced, excited-state reactions of toluene and benzyltrimethylsilane with 1,2-dimethyl-1-pyrrolinium perchlorate have been investigated. The results of these photoreactions have been interpreted in terms of steric, electrofugal group, and solvent effects upon the rates of competitive pathways available to initially formed radical cation pair intermediates. Finally, the photochemistry of benzyltrimethylstannane is described.