Selectivity in inter- and intra-molecular photocycloaddition of ethenes to benzenoid compounds

Abstract

The formation of isomers from the inter-and intra-molecular meta photocycloaddition of ethenes to the benzene ring has been specifically directed using the addend substituents in order to cause an asymmetric distortion of the C6 ring during the reaction, and to induce non-synchroneity into the addition process. The latter influence in the intramolecular reaction is achieved by the prese~ace of a heteroatom in the linking tether which also provides a convenient access to linear and angular heterotriquinanes. The meta photoaddition can be induced by sunlight exposure of appropriately substituted arene-ethene bichromophores.