Abstract: | The title compound, catena‐poly[[[diaqua(methanol‐κO)copper(II)]‐μ‐N‐(4‐methylpyrimidin‐2‐yl‐κN1)pyrazin‐2‐amine‐κ2N1:N4] [[aqua(aqua/methanol‐κO)(perchlorato‐κO)copper(II)]‐μ‐N‐(4‐methylpyrimidin‐2‐yl‐κN1)pyrazin‐2‐amine‐κ2N1:N4] tris(perchlorate) methanol monosolvate 1.419‐hydrate], {[Cu(C9H9N5)(CH3OH)(H2O)2][Cu(C9H9N5)(ClO4)(CH3OH)0.581(H2O)1.419](ClO4)3·CH3OH·1.419H2O}n, is a one‐dimensional straight‐chain polymer of N‐(4‐methylpyrimidin‐2‐yl)pyrazin‐2‐amine (L) with Cu(ClO4)2. The complex consists of two crystallographically independent one‐dimensional chains in which the CuII atoms exhibit two different octahedral coordination geometries. The L ligand coordinates to two CuII centres in a tridentate manner, with the pyrazine ring acting as a bridge linking the CuII coordination units and building an infinite one‐dimensional chain. Extensive hydrogen bonding among perchlorate anions, water molecules and L ligands results in three‐dimensional networks. |