The construction of substituted Anthracenes and their photochemical applications

The photodimerisation of anthracene is a reversible bimolecular process. Once dimerised, the monomeric anthracene may be reformed either thermally or photochemically. In the past, this dimerisation process has exhibited poor selectivity: when mixtures of substituted anthracenes are irradiated together a mixture of dianthracene products are formed. The research in this thesis describes the development of substituted anthracene systems that allow for an effective control over this dimerisation process. When irradiated, pairs of anthracenes yield only a single cross-cyclomer photoproduct. Two techniques to achieve this desired reactivity were developed: the first is based on the use of orthogonal steric bulk, and the second exploits the differences in the UV-absorbances of the compounds to allow selective excitation of only a single reacting species. Both of these routes achieved the desired results yielding only the one desired cyclomer. Studies examining the reversibility of these structures were also undertaken. The structures were found to be reversible both thermally and photochemically.