Crystal structures and thermogravimetric analyses of six CuCN network structures with protonated N-alkylethanolamines as guest cations.

The structures of six triperiodic CuCN network structures with conjugate acids of four N-alkylethanolamines as guest cations are described, namely, poly[2-hydroxyethan-1-aminium [μ3-cyanido-di-μ2-cyanido-dicuprate(I)]], {(C2H8NO)[Cu2(CN)3]}n, 1, poly[bis(2-hydroxy-N-methylethan-1-aminium) [di-μ3-cyanido-tri-μ2-cyanido-tricuprate(I)] monohydrate], {(C4H12NO)2[Cu3(CN)5]·H2O}n, 2, poly[tetrakis[N-(2-hydroxyethyl)ethan-1-aminium] [chloridotetra-μ3-cyanido-penta-μ2-cyanido-tricuprate(I)]], {(C4H12NO)4[Cu6(CN)9Cl]}n, 3, poly[tetrakis[N-(2-hydroxyethyl)ethan-1-aminium] [penta-μ3-cyanido-hepta-μ2-cyanido-octacuprate(I)]], {(C4H12NO)4[Cu8(CN)12]}n, 4, poly[2-hydroxy-N,N-diisopropylethan-1-aminium [μ3-cyanido-μ2-cyanido-dicuprate(I)] monohydrate], {(C8H20NO)[Cu3(CN)4]·H2O}n, 5, and poly[2-hydroxy-N,N-diisopropylethan-1-aminium [μ3-cyanido-di-μ2-cyanido-dicuprate(I)]], {(C8H20NO)[Cu2(CN)3]}n, 6. In five of the structures (1-5), the CuCN network includes Cu atoms occurring in pairs, linked by cuprophilic interactions. Analysis with the intent of exploring the `template effect' of the cations on the CuCN network structure indicated five separate CuCN topologies. The two different crystal structures involving cations from N-ethylethanolamine have the same basic topology, whereas the two crystal structures involving cations from N,N-diisopropylethanolamine have different topologies, contrary to what might be expected from a template effect. Thermogravimetric analysis of the compounds usually shows loss of HCN(g) and the free base by 200 °C, with a CuCN(s) residue, but decomposition of one of the structures is more complex.