Synthetic ion channels with rigid-rod π-stack architecture that open in response to charge-transfer complex formation

We describe the design, synthesis, and evaluation of synthetic ion channels with a new rigid-rod π-stack architecture that open in response to guest binding by aromatic electron donor-acceptor interactions. Highly cooperative and highly selective ligand gating is shown to yield anion selective, small ion channels that have the characteristic plum color of the charge-transfer complexes formed between the dialkoxynaphthalene ligands and the stacked naphthalenediimide acceptors of the channel. Copyright © 2005 American Chemical Society.