Crystal structures of two mixed-valence copper cyanide complexes with N-methyl-ethylenedi-amine

The crystal structures of two mixed-valence copper cyanide compounds involving N-methyl-ethylenedi-amine (meen), are described. In compound (I), poly[bis(μ₃-cyanido-κ₃C:C:N)tris(μ₂-cyanido-κ₂C:N)bis(N-methylethane-1,2-di-amine-κ₂N,N')tricopper(I)copper(II)], [Cu₄(CN)₅(C₃H₁₀N₂)₂] or Cu₄(CN)₅meen₂, cyanide groups link Cu^I atoms into a three-dimensional network containing open channels parallel to the b axis. In the network, two tetra-hedrally bound Cu^I atoms are bonded by the C atoms of two end-on bridging CN groups to form Cu₂(CN)₆ moieties with the Cu atoms in close contact at 2.560 (1) Å. Other trigonally bound Cu^I atoms link these units together to form the network. The Cu^II atoms, coordinated by two meen units, are covalently linked to the network via a cyanide bridge, and project into the open network channels. In the mol-ecular compound (II), [(N-methylethylenediamine-κ²N,N')copper(II)]-μ²-cyanido-κ²C:N-[bis(cyanido-κC)copper(I)] monohydrate, [Cu₂(CN)₃(C₃H₁₀N₂)₂]·H₂O or Cu₂(CN)₃meen₂·H₂O, a CN group connects a Cu^II atom coordinated by two meen groups with a trigonal-planar Cu^I atom coordinated by CN groups. The mol-ecules are linked into centrosymmetric dimers via hydrogen bonds to two water mol-ecules. In both compounds, the bridging cyanide between the Cu^II and Cu^I atoms has the N atom bonded to Cu^II and the C atom bonded to Cu^I, and the Cu^II atoms are in a square-pyramidal coordination.