The Pschorr Reaction, a Fresh Look at a Classical Transformation

The Pschorr reaction is a classical ring closure process for the formation of polycyclic systems in which two aryl moieties are joined together. It represents a bridge that connects diazonium ion chemistry with PAH synthesis. The Pschorr reaction has been employed as a key step in a number of carbocyclic and heterocyclic ring forming transformations for the synthesis of complex polycyclic molecules. Our continuing interest in diazonium ion chemistry and PAH chemistry prompted us to review the status of this transformation and to summarize the more recent developments in the use of this classical reaction.