Valenzisomere aromatischer Systeme

Über die Chemie des Benzvalens

Abstract

A short account of the more recent chemistry of benzvalene is provided with the exclusion however of photochemical processes. In the first part we report on the lithiumorganic synthesis of benzvalene and a series of closely related compounds. The mechanism, scope, and limitations of the ‘"Katz reaction” are discussed. Thereafter we review briefly the electrophilic additions of benzvalene. Distinction is made between those occurring with conservation of the bicyclobutane unit and those accompanied by skeletal rearrangement. The subsequent section is dedicated to the transition metal catalyzed benzvalene → fulvene rearrangement and to the benzvalene automerization reaction. The final paragraph comments on the C–H acidity and the related ¹³C–¹H coupling constants of benzvalene and a few similar valenes.