Overcooking

Overcooking is a term from chemistry, more precisely from organic chemistry . The boiling of aryldiazonium salts is understood to mean the thermal decomposition of their aqueous solutions when they are heated , with phenols usually only being formed in moderate yields via highly reactive phenyl cations .

Overview reaction

The reaction shows how phenol is formed in several reaction steps - using the example of the phenyldiazonium salt :

The reaction can be transferred to the production of other hydroxy-substituted aromatics from aryldiazonium salts.

mechanism

When an aqueous solution of the phenyldiazonium salt ( 1 ) is heated, nitrogen is split off and a very unstable phenyl cation ( 2 ) is formed. Water attacks 2 nucleophilically with formation of the oxonium ion 3 . The anion of the phenyldiazonium salt - in the example chloride - deprotonates the oxonium ion 3 , with phenol ( 4 ) being formed.

Individual evidence

1. ↑ Jonathan Clayden, Nick Greeves, Stuart Warren, Peter Wothers: Organic Chemistry , Oxford University Press, 2001, p. 598, ISBN 978-0-19-850346-0 .
2. ↑ Entry on diazonium compounds. In: Römpp Online . Georg Thieme Verlag, accessed on June 18, 2014.