 ##  [Electrophilic Aromatic Substitution](/electrophilic-aromatic-substitution) 

  ##  [Electrophilic Aromatic Substitution](https://natural.quantumdictionary.io/electrophilic-aromatic-substitution-0) 

  
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**Natural &amp; Formal Sciences Dictionary**

 
Definition

A class of reactions in which an electrophile replaces a hydrogen (or other substituent) on an aromatic ring by initial electrophile addition to form a non‑aromatic sigma complex (arenium ion) followed by deprotonation or loss restoring aromaticity.