Term: amidium ions
https://doi.org/10.1351/goldbook.A00268

Definition:
Cations formally derived by the addition of one hydron to the N or O atom of an amide and N-hydrocarbyl derivatives thereof. In organic chemistry an unspecified amidium ion is commonly a carboxamidium ion A00268-1.png or A00268-2.png The term does not imply knowledge concerning the position of the cationic centre, e.g. PhC(=O)N+Me3 N,N,N-trimethylbenzamidium.

Related Terms:
1) hydron (http://doi.org/10.1351/goldbook.H02904).
2) amide (http://doi.org/10.1351/goldbook.A00266).
3) hydrocarbyl (http://doi.org/10.1351/goldbook.H02891).

Images:
1) Not defined (https://goldbook.iupac.org/img/inline/A00268-1.png) 
2) Not defined (https://goldbook.iupac.org/img/inline/A00268-2.png) 

Source: PAC, 1995, 67, 1307. 'Glossary of class names of organic compounds and reactivity intermediates based on structure (IUPAC Recommendations 1995)' on page 1315 (https://doi.org/10.1351/pac199567081307)

Citation: 'amidium 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.A00268

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