Cyaarside

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.

Cyaarside anion

Names
Preferred IUPAC name Cyaarside
Systematic IUPAC name Arsenidocarbonate(II)
Other names Cyarside[1]
Identifiers
3D model (JSmol)	Interactive image
InChI InChI=1S/CAs/c1-2/q-1 Key: LSOQRAIANSLHSE-UHFFFAOYSA-N
SMILES [As]#[C-]
Properties
Chemical formula	CAs−
Molar mass	86.933 g·mol−1
Conjugate acid	Methylidynearsine
Related compounds
Related compounds	CP− CN− As≡C−As2−
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). Infobox references

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.^[2] Reaction of the uranium complex [((^Ad,MeArO)₃N)U^III(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

• arsaalkyne (R−C≡As)