A Remarkably Long-Lived Benzyl Carbanion

Abstract

[structure: see text] The photochemistry of ketoprofen, a widely used nonsteroidal antiinflammatory drug (NSAID) has been the subject of several studies as a result of its known phototoxicity. Photolysis of ketoprofen leads to 3-ethylbenzophenone, a process that is mediated by a short-lived carbanion. We have found that under carefully controlled conditions in THF, the lifetime of the carbanion can be extended to several hours, thus providing a powerful tool for studying the mechanism of its formation and subsequent reactions.