Cyaarside, also called cyarside, is the −C≡As anion. Featuring a triple bond between arsenic and carbon, it is the arsenic analogue of cyanide and cyaphide.

Preparation

An actinide cyaarside complex can be prepared by C−O bond cleavage of the arsaethynolate anion [OCAs]−, the arsenic analogue of cyanate and phosphaethynolate. Reaction of the uranium complex [((Ad,MeArO)3N)UIII(DME)] with one molar equivalent of [Na+[OCAs]−(dioxane)2.5] in the presence of 2.2.2-cryptand results in the formation of a dinuclear, oxo-bridged uranium complex featuring a C≡As ligand.[clarification needed]

See also