Term: arenium ions
https://doi.org/10.1351/goldbook.A00436

Definition:
Arenium σ-adducts (Wheland intermediates) (which are considered to be intermediates in electrophilic aromatic substitution reactions) and other cyclohexadienyl cations. A00436-1.png

Related Terms:
1) cyclohexadienyl cations (http://doi.org/10.1351/goldbook.C01502).
2) adduct (http://doi.org/10.1351/goldbook.A00138).
3) hydron (http://doi.org/10.1351/goldbook.H02904).

Image: nitrobenzenium ion (https://goldbook.iupac.org/img/inline/A00436-1.png) 

Source: 

Citation: 'arenium ions' in IUPAC Compendium of Chemical Terminology, 5th ed. International Union of Pure and Applied Chemistry; 2025. Online version 5.0.0, 2025. https://doi.org/10.1351/goldbook.A00436

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