Synthesis and solid-state structure of magnesium and calcium imidazole complexes

Three octahedral complexes built from N-alkylsubstituted imidazoles and magnesium as well as calcium chloride are reported. The obtained solid-state structures differ significantly from each other, depending on the size of the metal ion and the substituent on the imidazole. A chloro-bridged structure is found in the case of tert-butylimidazole, while for the iso-propylimidazole the calcium ion is coordinated by six imidazoles. For the smaller magnesium cation, we also found a sixfold coordination, but here only three of the iso-propylimidazoles coordinate to the magnesium, the three other positions are taken by water molecules. (C) 2007 Elsevier B.V. All rights reserved.