Photochemistry of Unsaturated Carbonyl Derivatives and Related Small Ring Systems

摘要

The photofragmentation of a variety of small ring homoand heterocyclic systems including cyclopropanes, epoxides, aziridines, oxaziranes and episulfides were studied. The photorearrangement of cyclopropanes to olefins and the photoinduced conversion of cyclopropenes to indenes were also examined. The studies are complementary and those parameters which determine the reaction course are defined in each case. For example, it is of interest to determine why certain cyclopropanes fragment to carbenes and others simply rearrange to isomeric olefins. Many of those reactions described have synthetic utility and heretofore inaccessible systems were synthesized. The photo-fragmentation of stilbene oxide is illustrative and appears to be the method of choice for preparing phenylcarbenes and thus phenylcyclopropanes and cyclopropenes. (Author)