Argentivorous molecules bearing two aromatic side-arms: Ag-π and CH-π interactions in the solid state and in solution

Seven double-armed cyclens bearing two aromatic side-arms, at the 1- and 7-positions of the cyclens, were prepared via three steps from dimethyl 2,2′-iminodiacetate. The X-ray structures of the Ag complexes and Ag-ion-induced H NMR spectral changes suggest that the two aromatic side-arms cover the Ag ions incorporated in the ligand cavities, as if the aromatic ring "petals" catch the Ag ions in the way a real insectivorous plant (Venus flytrap) catches insects, using two leaves. It is also reported that the CH-π interactions between the aromatic side-arms, as well as the Ag-π interactions, are crucial for double- and tetra-armed cyclens to work as argentivorous molecules. © 2013 American Chemical Society.