Studies on the Control of Photoinduced Electron Transfer Reaction of Porphyrins by Amphiphilic Polyelectrolytes

环十二烷基（Cd）基团，庞大的和刚性的疏水基团的环状结构，共价连接到聚磺酸被发现在水溶液中形成疏水簇，由于自组织。因此，聚合物作为整体形成单分子胶束。锌（II）四苯基卟啉（ZnTPP）部分共价连接到这样的两亲性聚磺酸被发现是紧密分隔在镉簇，导致非常不寻常的光物理和光化学性质。特别反常的行为是磷光和E-型延迟荧光，由于从三重态激发态的热再布居发射的隔室化的ZnTPP部分在水溶液中，在室温下。这些不寻常的观察结果主要是由于三重态-三重态湮灭被严格防止的事实，因为发色团在Cd簇中彼此静态隔离，并且还被保护免受本体水相的影响，使得ZnTPP三重态几乎没有机会彼此相遇，并且还在其寿命期间被保护免受本体相中的杂质的影响。这导致即使在室温下的流体水溶液中也有极长的三重态寿命。在光诱导的电子转移从ZnTPP的长寿命的三重态的锍盐，自毁的电子受体，通过激光光解研究，发现发生有效的电子转移，并产生自由基来自ZnTPP和受体。这种分区化的ZnTPP系统的一个特征是ZnTPP阳离子自由基持续极长时间（通过ESR识别自由基几个小时）。

Cyclododecyl (Cd) groups, bulky and rigid hydrophobic goups with a ring structure, covalently attached to a polysulfonic acid were found to form hydrophobic clusters in aqueous solution due to self-organization. Thus, the polymer, as a whole, forms unimolecular micelle. Zinc(II) tetraphenylporphyrin (ZnTPP) moieties covalently linked to such an amphiphilic polysulfonic acid were found to be tightly compartmentalized in the Cd clusters, leading to very unusual photophysical and photochemical properties. Particularly anomalous behavior was that phosphorescence and E-type delayd fluorescence due to thermal repopulation from the triplet-excited state were emitted by the compartmentalized ZnTPP moieties in aqueous solution at room temperature. These unusual observations are primarily due to the fact that triplet-triplet annihilation is rigorously prevented because the chromophores are statically isolated in the Cd cluster from each other and also protected from the bulk aqueous phase such that the ZnTPP triplets have virtually no chance to encounter each other and also protected from impurities in the bulk phase during their lifetimes. This leads to enormously long triplet lifetime even in fluid aqueous solution at room temperature. In the photoinduced electron transfer from the ZnTPP long-lived triplets to sulfonium salts, self-destructive electron acceptors, as studied by laser photolysis, efficient electron transfer was found to occur and generate radicals coming from the ZnTPP and the acceptors. A characteristic feature of this compartmentalized ZnTPP system was that the ZnTPP cation radical persisted for extremely long time (the radical was recognized for several hours by ESR).