A flexible dibenzo-O4S2-macrocycle: twist-and-squeeze type metal binding via synergic action of metal–ligand and metal–π interactions

A 21-membered O 4 S 2 -donor-macrocycle ( L ) incorporating a dibenzo-subunit was synthesized. From the reaction of L with AgPF 6 , an endo -type 1:1 complex [Ag L ]PF 6 ( 1 ) was obtained. On complexation, the conformation of L changes dramatically due to metal–ligand coordination as well as π-interactions between the metal and the dibenzo-subunit from L . This unique change in configuration showing a twist-and-squeeze type process illustrates how large flexible ligands stabilize complexes through conformational changes.