Reaction of a ligand which contains two N-donor and O-donor tridentate domains separated by a 1,3-phenylene spacer unit with Zn(2+) ions results in a pentanuclear circular helicate [Zn(5)(L)(5)](10+) and this structure persists in both the solid and solution state. The formation of this high nuclearity species is governed by unfavourable steric interactions between the phenyl units which destabilize the simple linear helicate. Incorporation of enantiopure units within the ligand strand controls the diastereoselectivity with up to 80% d.e.

In the title compound, [ReCl(C15H16N4)(CO)3], the ReI ion is coordinated in a distorted octa­hedral geometry by one Cl atom, two N atoms of the bidentate ligand and three carbonyl groups. The cyclo­pentane group is orientated in a transoid fashion with respect to the chloride ligand. The dihedral angle between the pryridine rings is 10.91 (12)°. In the crystal, N—H⋯Cl hydrogen bonds link complex mol­ecules, forming a two-dimensional network parallel to (001).

In the title compound, [ReCl(C16H18N4)(CO)3], the ReI ion is coordinated in a distorted octa­hedral geometry by one Cl atom, two N atoms of the bidentate ligand and three carbonyl groups. The cyclo­hexane group is orientated in a transoid fashion with respect to the chloride ligand. In the crystal, N—H⋯Cl hydrogen bonds link complex mol­ecules, forming a two-dimensional network parallel to (100).