CuCN

Copper(I) cyanide (CuCN), also known as cuprous cyanide, is an inorganic compound consisting of copper in the +1 oxidation state bound to cyanide. It is a white to gray crystalline solid with low solubility in water. In the solid state, CuCN forms a polymeric network in which cyanide ligands bridge copper centers, producing a one‑dimensional Cu–CN chain. In solution, its behavior is governed by complexation; in cyanide-containing media, CuCN can dissolve by forming soluble copper cyanide complexes.

Preparation and occurrence: CuCN is typically prepared by precipitation from solutions of soluble copper(I) salts (such as CuCl or CuNO3) with cyanide sources (e.g., KCN or NaCN) under controlled conditions, followed by isolation of the crystalline solid. It can also be obtained as a byproduct or intermediate in routes that generate copper(I) cyanide species, and it is commonly handled as a solid reagent in inorganic synthesis.

Reactions and uses: CuCN serves as a convenient source of cyanide for the preparation of copper cyanide salts and various coordination compounds. It is used in inorganic and organocopper synthesis as a precursor to copper(I) cyanide complexes and related materials, including coordination polymers and catalysts. In research and industry, it provides a convenient solid cyanide reagent for preparative work and materials chemistry.

Safety: Cyanide compounds are highly toxic. Copper(I) cyanide should be handled with appropriate precautions to prevent ingestion, inhalation, or skin contact. If acids are added to solutions containing cyanide, hydrogen cyanide gas can be released, requiring proper ventilation and handling.