Cations derived formally by the addition of a hydron
or other cationic species to any position of an arene, e.g.
, benzenium. The term includes:
Arenium σ-adducts (Wheland intermediates) (which are considered to be intermediates in electrophilic aromatic substitution reactions) and other cyclohexadienyl cations.
Arenium π-adducts, such as:
PAC, 1995, 67, 1307
(Glossary of class names of organic compounds and reactivity intermediates based on structure (IUPAC Recommendations 1995))
on page 1318
PAC, 1994, 66, 1077
(Glossary of terms used in physical organic chemistry (IUPAC Recommendations 1994))
on page 1077