Arenium ions

{
  "id": "MLC-T-CHM-000778",
  "term": "Arenium ions",
  "field": "Chemistry",
  "definition": "Carbocation intermediates formed during electrophilic aromatic substitution reactions, where an electrophile adds to an aromatic ring. These ions, also known as sigma complexes or cyclohexadienyl cations, feature a positive charge delocalized over several carbon atoms of the ring. The arenium ion is typically a transient species that loses a proton to restore aromaticity.",
  "subject": "Organic and Biomolecular Chemistry",
  "see_also": [
    "aryl cations",
    "cyclohexadienyl cations",
    "hydron",
    "π-adduct",
    "σ-adduct"
  ],
  "references": [
    "PAC, 1995, 67, 1307. 'Glossary of class names of organic compounds and reactivity intermediates based on structure (IUPAC Recommendations 1995)' on page 1318 (https://doi.org/10.1351/pac199567081307)"
  ],
  "url": "https://mlchart.com/terminology/chemistry/arenium-ions/"
}