[1][2] Nitrenium ions are isoelectronic with carbenes, and can exist in either a singlet or a triplet state.

[3] Aryl nitrenium ions are of biological interest because of their involvement in certain DNA damaging processes.

The regiochemistry and energetics of the reaction of phenylnitrenium ion with guanine has been investigated using density functional theory computations.

For instance, they are formed upon treatment of chloramine derivatives with silver salts or by activation of aryl hydroxylamine derivatives or aryl azides with Brønsted or Lewis acids.

[6] The Bamberger rearrangement is an early example of a reaction that is now thought to proceed via an aryl nitrenium intermediate.