Poly[1,3-Dimethyltetrahydropyrimidin-2(1H)-iminium [tri-µ2-cyanido-κ6C:N-dicuprate(I)]]

The title compound contains a guanidinium cation that was unexpectedly found during X-ray single crystal analysis of a copper(I) cyanide network expected to contain protonated N,N’-dimethyl-1,3-diaminopropane. The cation was presumably formed by reaction of the amine with cyanide ions in the aqueous sodium cyanide/copper cyanide mixtures used in the synthesis. The structure of the network solid features the guanidinium cation as a guest in an anionic two-dimensional polymeric framework with stoichiometry Cu2(CN)3−. Confirmation of the structure was provided by analytical, thermal gravimetric and infrared data.