Nitrenium ion

A nitrenium ion (also called: aminylium ion) in organic chemistry is a reactive intermediate based on nitrogen with both an electron lone pair and a positive charge and with two substituents (R2N+). The compound can have both a singlet and a triplet state.

Aryl nitrenium ions are currently investigated because of their involvement in certain DNA damaging processes. These intermediates can have microsecond or longer lifetimes in water. Nitrenium ions are also intermediates in organic reactions for instance the Bamberger rearrangement. They can also act as electrophiles in electrophilic aromatic substitution.

The term imidonium ion with the same meaning is now obsolete.