Dehydrative Coupling of Alcohols by Iridium(III) Complexes with N-Heterocyclic-Pyridine Chelating Ligands Decorated with Naphthalene-Diimide

A series of dimetallic and monometallic Cp*Ir(III) complexes bearing naphthalene-diimide-decorated N-heterocyclic carbene/pyridine [NDI-(NHC-pyridine)] ligands were prepared characterized. The show a C,C-chelating coordination the NHC-pyridine ligand, with pyridine ring ligand bound to metal via cyclometallation rather than by its nitrogen atom, although atom could be achieved subjecting one reaction strong acid. spectroelectrochemical studies new compounds reveal that are able undergo two successive reduction events, associated sequential NDI moiety ligand. tested in dehydrative etherification cross-coupling primary alcohols, where they showed good activity selectivity toward cross-coupled products. mechanistic allowed us propose mechanism which likely involves redox-neutral acid-catalyzed pathway.