1971–1976 – Profiting from a New Beginning in Geneva

Abstract

A few projects of organic photochemistry, which have been investigated in Geneva in 1971–76, are reviewed summarily. They include excited state-selective processes from the n,?* and ?,?* triplets and selectively occurring ? ? ?* induced reactions of ?,?-unsaturated cyclic ketones, oxadi-?-methane rearrangements and 1,3-acetyl shifts of ?,?-unsaturated methyl ketones, and di-?-methane rearrangements of benzoylnaphthobarrelene compounds. Furthermore, intramolecular triplet energy transfer dependence on rigid donor–acceptor syn-anti topologies between indanone and naphthalene moieties most likely reflects competition between radiationless energy dissipation by through-space aromatic ? interaction (amounting to intramolecular exciplex action) and through-?-bond exchange transfer. Finally, electronically integrating actinometry and time-resolved IR spectroscopy of excited states and reaction intermediates are mentioned.