Homogeneous Perdehydrogenation and Perhydrogenation of Fused Bicyclic N‑Heterocycles Catalyzed by Iridium Complexes Bearing a Functional Bipyridonate Ligand

Homogeneous
perdehydrogenation of saturated bicyclic 2,6-dimethyl­deca­hydro-1,5-naph­thyridine
and perhydrogenation of aromatic 2,6-dimethyl-1,5-naph­thyridine
with release and uptake of five molecules of H2 are efficiently
achieved by iridium complexes bearing a functional bipyridonate ligand.
Successive perhydrogenation and perdehydrogenation of 2,6-dimethyl-1,5-naph­thryridine
using a single iridium complex also proceed with the reversible interconversion
of the catalytic species, depending on the presence or absence of
H2.