Imidoyl

Part of speech: noun

Definitions

1. A chemical group derived from an imidic acid, containing a carbon atom double-bonded to a nitrogen atom in organic chemistry
2. The univalent radical formed by removing the hydroxyl group from an imidic acid, used in naming organic compounds
3. An organic functional group with the structure RC(=NH)- that appears in many chemical compounds and their nomenclature

Etymology: Imidoyl is a chemical group built from the word "imide" plus the suffix "-yl." Imide itself comes from "amide," a nitrogen-containing compound, with the "im-" spelling reflecting the imine family of compounds, which contain a carbon-nitrogen double bond. The suffix "-yl" is the standard chemists' ending for a radical, a fragment of a molecule with one bond left free to attach to something else. The name follows the same pattern as "acetyl" and "methyl," where a parent compound's name is shortened and given "-yl" to mark it as a group rather than a complete substance. The "-yl" ending has an older history than the chemistry around it. It was used in the early 19th century, when Justus von Liebig and Friedrich Wöhler proposed "benzoyl" in 1832 for the group in benzoic acid, and the ending became a systematic way of naming the pieces left behind when a molecule loses atoms. Imidoyl follows that convention, so its name describes the structure directly: a group derived from an imide.