Cobalt Carbonyl Hydrides with 1,1'-Diphosphinylferrocene Ligands -- Structural and Electrochemical Diversity.

The reaction of Co(CO)₄H with various 1,1'-bis(diorganophosphanyl) ferrocenes (dopf) produces structurally different heterodinuclear (Co,Fe) compounds. In contrast to the P-isopropyl and P-cyclohexyl- substituted complexes [Co(CO)₂H(dopf)] described earlier, the P-phenyl-substituted analogue exhibits a structure in the crystal with the hydride in trans position to a P atom. Using the dopf precursor with bulky P-tert-butyl substituents, a heterotrinuclear species {(μ- dtbpf)[Co(CO)₃H]₂} is obtained, in which the ferrocene-containing ligand acts as a bridge. In addition to the comparative analysis of molecular structures the (spectro)electrochemical responses are discussed in the light of the mechanism established for the isopropyl-substituted system. [ABSTRACT FROM AUTHOR]