Insulated π-conjugated 2,2′-bipyridine transition-metal complexes: enhanced photoproperties in luminescence and catalysis

Abstract

2,2′-Bipyridine has been identified as a privileged ligand scaffold for photofunctional transition metal complexes. We herein report on the synthesis and photoproperties of an insulated π-conjugated 2,2′-bipyridine with a linked rotaxane structure consisting of permethylated α-cyclodextrin (PM α-CD) and oligo(p-phenylene ethynylene). The insulated π-conjugated 2,2′-bipyridine exhibited enhanced ligand performance in the solid-state emitting biscyclometalated Ir complexes and visible-light-driven Ni catalysts owing to π-extension and remote steric effects based on the linked rotaxane structure.