A new bis-coronand derived from biphenyl has been prepared and its complexing and sensing properties for alkaline, alkaline-earth and transition cations have been studied. Open and clamp complexes are formed depending on the cation size and complex stoichiometry. Both types of geometries can be distinguished due to their different fluorescent behaviour. Zn2+ gives rise to 1:1 and 1:2 complexes with a similar geometry.
- Conformational restriction