The coordination chemistry of 5-hydroxypyrazoline ligand precursor 1 with Ni(OAc)2·4H2O and 1,1-bis(diphenylphosphino)methane (DPPM) as co-ligand to form the monometallic nickel complex 2 [Ni(1–2H)(DPPM)] was studied. The complex was characterized and investigated by various techniques, pointing out a square planar geometry at the nickel center with η1-coordination of the DPPM ligand. Moreover, addition of Fe2(CO)9 revealed the formation of the bimetallic complex 3 [Ni(1–2H)(DPPM)Ni(1–2H)] with DPPM as bridging ligand between two nickel centers and the abstraction of one DPPM ligand by the iron to form Fe(CO)4(η1-dppm).