Iminium ion
An iminium salt or cation in organic chemistry has the general structure [R1R2C=NR3R4]+ and is as such a protonated or substituted imine. It is an intermediate in many organic reactions such as the Beckmann rearrangement, Vilsmeier-Haack reaction, Stephen reaction or the Duff reaction. The use of the alternative names imonium compounds and immonium compounds is discouraged.
Iminylium ions have the general structure R2C=N+. They form a subclass of nitrenium ions.
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