Palladium(II)-Directed Self-Assembly of Dynamic Donor−Acceptor [2]Catenanes

Highly efficient syntheses of donor−acceptor [2]catenanes were developed using a combination of templation and reversible metal−ligand coordination. The desired [2]catenanes were obtained within minutes through a five-component assembly, involving a donor-containing crown ether, an acceptor-containing ligand, two Pd(II) metal centers, and a dipyridyl ligand. The [2]catenane formation was characterized by ¹H NMR and UV−vis spectroscopies and cold-spray ionization mass spectrometry. In particular, great translational selectivity was observed when a crown ether with two different donor units was employed.