Gondola-Shaped Luminescent Tetrarhenium Metallacycles with Crown-Ether-like Multiple Recognition Sites

The self-assembly of gondola-shaped tetrarhenium metallacyclophanes was achieved in near quantitative yield from Re(CO)₃ corners, a ditopic heterocyclic clip, and a bischelating-bridging unit using an orthogonal-bonding approach. The highly luminescent metallacycles contain crown-ether-like recognition sites, which are capable of selectively recognizing metal ions and planar aromatic molecules.