Enhanced Silver Ion Binding to a Rigid Bisarene Molecular Cleft with Formation of Nonpolar Pleated Sheets through Non-Ionic Intermolecular Forces

Silver ion complexation to bisarene ligands is enhanced by providing a conformationally rigid molecular cleft in the (Z)-acenaphthylene dimer 1. NMR titrations were used to determine complexation constants K for a series of ligands in tetrahydrofuran solution, with K = 4.9 M-1 for the Z dimer 1 and 0.4 M-1 for the E dimer 2. Higher values of K were observed in CDCl3/CD3OD 9:1 with K = 38 M-1 for 1 and K = 4.1 M-1 for 2. In the solid state, isolated clusters of [1·(AgCF3SO3)2]2 form a novel, pleated-sheet motif based on non-ionic interactions between clusters.