X-ray diffraction study of bisphosphonate metal complexes: Mg and Ca complexes of (dichloromethylene)bisphosphonic acid P,P′-diisopropyl ester

Preparation and X-ray structural characterisation of Mg(II) and Ca(II) complexes of P,P′-diisopropyl(dichloromethylene)bisphosphonate, [Na2Mg{Cl2C(PO3iPr)2}2(H2O)4]n (1) and [{Ca2[Cl2C(PO3iPr)2]2(EtOH)2(H2O)2} · H2O]2 (2) were carried out. Compound 1 consists of one-dimensional chains along the c-direction, and compound 2 is a tetramer; the bisphosphonato ligand acts as chelating and bridging ligand in both compounds.