Something to note is that complex 3 features a neutral naphthyridine backbone, as is evidenced by the C1-C2 and C9-C10 distances of 1.496(5) and 1.504(4) Å, similar to what was observed in complex 1. Considering that complex 3 can be synthesized from complex 2 using only diethyl silane (Scheme 3), this implies that one of the protons on the methylene linker originates from the silane in this case. It is not completely clear what the mechanism of the formation of 3 is, however, it seems possible that at some point a Co-H intermediate is formed in which the hydride is sufficiently acidic to protonate the backbone. Alternatively, a radical reaction in which a H-atom is transferred from cobalt to the backbone is also possible.