imidoyl

Imidoyl refers to a functional group in organic chemistry that is the acyl-imine fragment, typically represented as R-C(=NR')-. The imidoyl group is derived from imidic acids and is related to amide and imidate chemistry. Structurally, the carbon bearing the imidoyl moiety is sp2-hybridized and bears a double bond to nitrogen, with the substituent NR' on the nitrogen. When this carbon carries a leaving group such as chlorine, the species is described as an imidoyl chloride (for example, acetimidoyl chloride, CH3-C(=NH)Cl).

Commonly encountered imidoyl derivatives include imidoyl chlorides and related reagents used to introduce the imidoyl fragment into molecules. The general formula for a simple imidoyl chloride is R-C(=NR')-Cl, where R is an organic substituent and NR' is the imine nitrogen substituent. Examples include formimidoyl chloride (H-C(=NH)Cl) and acetimidoyl chloride (CH3-C(=NH)Cl).

Reactivity and applications: Imidoyl chlorides are typically highly reactive toward nucleophiles. They are used as intermediates in the synthesis of amidines by reaction with amines, and they can also react with alcohols to form imidate esters under appropriate conditions. In hydrolytic or basic environments, imidoyl groups can be converted to other carbonyl-containing functionalities, such as amides, depending on the reaction conditions. In addition to organic synthesis, imidoyl ligands can appear in coordination chemistry, where the imidoyl fragment can function as a donor group to metal centers in certain complexes.

See also: amidines, imidoyl chloride, imidate, acylimine.