Cover Picture: Benzannulation Reactions: A Case for Perspective Change From Arene Decoration to Arene Construction (Chem. Rec. 1/2022)

Abstract

The cover picture shows recreations of the ancient symbol ‘ouroboros'. The most common depiction of the latter, a snake swallowing its own tail, is perhaps the oldest allegorical symbol in renaissance alchemy. August Kekulé's subconscious deciphered the structure of benzene by invoking this very symbol in his famous daydream. Chemists who endeavour to synthesize arenes can also draw inspiration from ouroboros, as depicted here. At their disposal are numerous acyclic building blocks (snakes) that may be combined to form substituted arenes by benzannulation reactions, a versatile alternative to aromatic substitutions. See the review by R. Menon and co-workers (DOI: 10.1002/tcr.202100249).