A novel bipyridine-based hexadentate tripodal framework with a strong preference for trigonal prismatic co-ordination geometries.

The synthesis of the novel ligand tris(2,2'-bipyrid-6-yl) methanol (L(1)) is described. Co-ordination of the ligand to the first row transition metals (Mn(2+)-Zn(2+)) as well as Cd(2+) showed that the ligand formed complexes close to trigonal prismatic in geometry in the solid state. Analysis of the geometry of the co-ordination spheres showed varying degrees of trigonal prismatic and octahedral character. For each d-electron configuration, this could be related to the relative differences in ligand field stabilisation energies for the two geometries.