Crystal structures of 4-phenyl-piperazin-1-ium 6-chloro-5-ethyl-2,4-dioxopyrimidin-1-ide and 4-phenyl-piperazin-1-ium 6-chloro-5-isopropyl-2,4-dioxopyrimidin-1-ide.

The title mol-ecular salts, C10H15N2 (+)·C6H6ClN2O2 (-), (I), and C10H15N2 (+)·C7H8ClN2O2 (-), (II), consist of 4-phenyl-piperazin-1-ium cations with a 6-chloro-5-ethyl-2,4-dioxopyrimidin-1-ide anion in (I) and a 6-chloro-5-isopropyl-2,4-dioxopyrimidin-1-ide anion in (II). Salt (I) crystallizes with two independent cations and anions in the asymmetric unit. In the crystal structures of both salts, the ions are linked via N-H⋯O and N-H⋯N hydrogen bonds, forming sheets which are parallel to (100) in (I) and to (001) in (II). In (I), the sheets are linked via C-H⋯Cl hydrogen bonds, forming a three-dimensional framework.