Synthesis and structural characterisation of Group I and II metal complexes involving the ligand tris(2-pyridylmethyl)amine

The first successful crystallisation and structure characterisation of prot onated tris(2-pyridylmethyl)amine (TPA), [H(3)TPA][SO4][NO3], has been achi eved. The reaction of the ligand with Group I and II metal salts led to the formation of either 1 : 1 or 1 :2 metal to ligand complexes. One such 1 :2 complex, [Ca(TPA)(2)][ClO4](2) 2, has been structurally characterised. The ionic radius of the metal can be used in predicting the solid state struct ure of the complexes resulting from reactions involving metal salts and thi s ligand. If the ionic radius of the metal ion is greater than 0.9 Angstrom , then the preferentially formed complex will have a metal to ligand ratio of 1 :2.