Water-soluble dendrimers as photochemical reaction media: Chemical behavior of singlet and triplet radical pairs inside dendritic reaction cavities
Water-soluble dendrimers as photochemical reaction media: Chemical behavior of singlet and triplet radical pairs inside dendritic reaction cavities
复制标题
DOI：
10.1021/ja049492w
复制
发表时间：
2004-07-28
影响因子：
15
通讯作者：
Ramamurthy, V
中科院分区：
文献类型：
--
作者：
Kaanumalle, LS;Nithyanandhan, J;Ramamurthy, V
水溶性聚（烷基芳基醚）树状大分子在水介质中作为有机底物的宿主已被探索。研究了典型的光反应，即(a) 1-萘酰苯甲酸酯和(b) 1-萘酰苯甲酸酯的光-炸薯条反应和(a)二苯酮和(b)苯甲酸烷基醚的α -裂解反应。我们发现树突状微环境不仅限制了自由基中间体的迁移，而且严格地封装了底物、中间体和产物，使其不“泄漏”到体环境中。对胶束介质中相同光反应的比较研究表明，树突介质比胶束介质具有更好的约束。
Water-soluble poly(alkyl aryl ether) dendrimers have been explored for their use as hosts of organic substrates in aqueous media. Prototypical photoreactions, namely, photo-Fries reaction of (a) 1-naphthyl benzoate and (b) 1-naphthyl phenyl ester and alpha-cleavage reaction of (a) dibenzyl ketones and (b) benzoin alkyl ethers, have been examined. We find that a dendritic microenvironment not only restricts the mobility of radical intermediates but also rigidly encapsulates the substrate, intermediates, and products from "leaking" to the bulk environment. Comparative studies of the same photoreactions in micellar media demonstrate that dendritic media offer much better constrainment than the micelles.