It exists in two polymorphs both of which contain -[Cu-CN]- chains made from linear copper(I) centres linked by cyanide bridges.

These complexes contrast with those of silver and gold cyanides, which form [M(CN)2]− ions in solution.

[11] Copper cyanide is also soluble in concentrated aqueous ammonia, pyridine and N-methylpyrrolidone.

It reacts with organolithium reagents to form "mixed cuprates" with the formulas Li[RCuCN] and Li2[R2CuCN].

The mixed cuprates Li[RCuCN] and Li2[R2CuCN] function as sources of the carbanions R−, but with diminished reactivity compared to the parent organolithium reagent.

[13] CuCN has also been introduced as a mild electrophilic source of nitrile under oxidative conditions, for instance secondary amines[14] as well as sulfides and disulfides[15] have been efficiently cyanated using this methodology.