Supramolecular organic and inorganic photochemistry: Radical pair recombination in micelles, electron transfer on starburst dendrimers, and the use of DNA as a molecular wire

Abstract

Supramolecular chemistry is concerned with systems for which non-covalent interactions become significant or dominate in determining the chemistry of the guest/host systems. Supramolecular photo chemistry is concerned with systems where non-covalent interactions become significant or dominate in determining the observed photochemistry. The supramolecular photochemistry of ketones adsorbed in micelles and of metal complexes adsorbed on starburst dendrimers and DNA is the subject of this report. Supramolecular photochemistry offers the photochemist an opportunity to both quantitatively and qualitatively modify the photochemistry of systems whose molecular photochemistry has been well established. Thus, a famous secondary photochemical process, the geminate combination reactions of radical pairs and a famous primary photochemical process, the electron transfer between a photoexcited donor and a ground state acceptor, could be used to probe deeply the structure of micelles on the one hand and the structure of starburst dendrimers and DNA on the other. The notion that true supramolecular systems require more than an understanding of the additive chemistry of the molecular systems is clearly evident in these investigations. In the case of radical pairs in supercages, the role of interacting spin, molecular and chemical dynamics and the size of the supercage are made clear by a quantitative model. © 1995 IUPAC