A CIDEP Study on the Photosensitized Reaction of Maleimide with Xanthone: Addition Effect of Hydrochloric Acid
A CIDEP Study on the Photosensitized Reaction of Maleimide with Xanthone: Addition Effect of Hydrochloric Acid
复制标题
马来酰亚胺与氧杂蒽酮光敏反应的CIDEP研究：盐酸加成效应
DOI：
10.1246/bcsj.73.37
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发表时间：
2000
影响因子：
4
通讯作者：
K. Mukai
中科院分区：
文献类型：
--
作者：
K. Ohara;S. Nagaoka;K. Mukai
用时间分辨EPR方法研究了马来酰亚胺（MI）与氧杂蒽酮（Xn）在异丙醇中的光敏化反应。在纯2-丙醇中观察到的发射CIDEP光谱主要归属于两种MI烷基型自由基。另一方面，MI阴离子自由基的吸收光谱已经在2-丙醇包括盐酸中新观察到。盐酸的加入效应表明Xn对MI的光敏化存在两种机制。一种是典型的三重态-三重态能量转移，随后由MI的三重态从溶剂中夺取氢。另一个是电子转移过程，MI从主要由三重态Xn与HCl的快速反应产生的Xn酮基自由基。基于这些光敏化过程的自旋极化转移机制可以成功地解释目前的CIDEP结果。还研究了水和增感剂对上述反应的影响。
The photosensitized reaction of maleimide (MI) with xanthone (Xn) in 2-propanol was investigated by the time-resolved EPR method. The emissive CIDEP spectrum observed in neat 2-propanol is predominantly assigned to two kinds of MI alkyl-type radicals. On the other hand, the absorptive spectrum of the MI anion radical has been newly observed in 2-propanol including hydrochloric acid. The addition effect of hydrochloric acid indicates the existence of two mechanisms for the photosensitization of MI by Xn. One is a typical triplet-triplet energy transfer followed by hydrogen abstraction by the triplet state of MI from the solvent. The other is an electron-transfer process to MI from the Xn ketyl radical produced primarily by a fast reaction of the triplet Xn with HCl. The spin-polarization transfer mechanism based on these photosensitization processes can successfully explain the present CIDEP results. The effect of water and the sensitizer dependence on the above reaction were also investigated.