Photo-induced Electron-relay Reaction Utilizing Electrostatic Field of Polymers

聚苯乙烯磺酸盐阴离子（PSS^-）和芪唑阳离子（Stz^+）之间通过静电相互作用形成分子聚集体。共吸附敏化剂Ru（bpy）_3^<2+> 2+在辐照下将其电子转移到苯乙烯唑阳离子上，形成苯乙烯唑自由基。在烯烃聚集体之间发生有效的电子中继，并且发生烯烃的高效顺式到反式异构化，量子产率高达100。首先，我们可以证明，与PSS^-结合的数千个Stz^+离子被分成胶束状团簇的小聚集体，并且它们的聚集数在80-90范围内恒定，与PSS^-的聚合度无关。电子中继链异构化在一个胶束簇内进行。其次，我们可以成功地直接检测苯乙烯基，作为一个不稳定的瞬态中间体的顺反异构化。对二氰基苯（DCB）和萘的混合物在芪阳离子存在下的光解以<lambda>DCB的阴离子自由基（λ max 340 nm）为代价产生了一个瞬态物种（λ max 420 nm<lambda>）。瞬态光谱是苯乙烯基，衰减满足二级动力学。已发现的衰减速率常数大大增加，通过添加聚苯乙烯磺酸盐阴离子，这意味着电子被迅速中继之间的吸附stilbazolium离子聚集体。

Molecular aggregates are formed between polystyrenesulfonate anions (PSS^-) and stilbazolium cations (Stz^+) by means of their electrostatic interactions. A co-adsorbed sensitizer, Ru(bpy)_3^<2+> 2+ transfers, on irradiation, its electron into stilbazolium cation resulting in the formation of stylbazole radical. An efficient electron relay takes place among the olefin aggregates, and highly efficient cis to trans isomerization of the olefins occurs, quantum yields being as high as 100. Firstly, we could show that the thousands of Stz^+ ions bound to PSS^- are divided into small aggregates of micelle-like clusters and that their aggregation numbers are constant in the range of 80-90, irrespective of the degree of polymerization of PSS^-. The electron-relay chain isomerization proceeds within one micellar cluster. Secondly, we could succeed in detecting directly stylbazole radical, as an unstable transient intermediate in the cis-trans isomerization. Photolysis of a mixture of p-dicyanobenzene (DCB) and naphthalene in the presence of stilbazolium cation yielded a transient species, (^<lambda>max 420 nm) at the expense of anion radical of DCB (^<lambda>max 340 nm). The transient spectrum is that of stylbazole radical, and decays satisfying a second-order kinetics. The decay rate constant has been found to be heavily increased by the addition of polystyrenesulfonate anions, which implies that an electron is rapidly relayed among the adsorbed stilbazolium ion aggregates.