Crystal structure of catena-poly[[[(2-eth­oxy­pyrazine-κN)copper(I)]-di-μ(2)-cyanido] [copper(I)-μ(2)-cyanido]]

In the asymmetric unit of the title coordination compound, {[Cu(CN)(C(4)H(3)OC(2)H(5)N(2))][Cu(CN)]}(n), there are two Cu atoms with different coordination environments. One Cu(I) ion is coordinated in a triangular coordination geometry by the N atom of the 2-eth­oxy­pyrazine mol­ecule and by two bridging cyanide ligands, equally disordered over two sites exchanging C and N atoms, thus forming polymeric chains parallel to the c axis. The other Cu atom is connected to two bridging cyanide groups disordered over two sites with an occupancy of 0.5 for each C and N atom, and forming an almost linear polymeric chain parallel to the b axis. In the crystal, the two types of chain, which are orthogonal to each other, are connected by cuprophilic Cu⋯Cu inter­actions [2.7958 (13) Å], forming two-dimensional metal–organic coordination layers parallel to the bc plane. The coordination framework is further stabilized by weak long-range (electrostatic type) C—H⋯π inter­actions between cyano groups and 2-eth­oxy­pyrazine rings.