Catalytic oxidations using cobalt(II) complexes - Advances in Catalytic Activation of Dioxygen by Metal Complexes - page 275

The NO coordinates to the Co at the axial site trans to the bridging dmf
oxygen, providing a six-coordinate geometry at the metal.

The nitrosyl complex is oxidized with molecular oxygen to the nitro
complex

3.5 Oxidative dehydrogenation

In -saturated dmf solution, the Co(II) complex of the tetrahydrosalen
ligand undergoes slow oxidative dehydrogenation at both C-N
bonds and the cobalt(II) salen complexes (CoL) are formed 35 (Figure 12).
The overall process is autocatalytic and involves reduction of to water,

but is probably an intermediate.