Polarographic behaviour of π-allylic complexes of transition metals : II. π-allyltricarbonylcobalt and some phosphinic derivatives

The polarographic reduction in acetonitrile (ACN) of π-C₃H₅Co(CO)₃ and of the phosphinic derivatives π-C₃H₅Co(CO)₂L L = P(OC₆H₅)₃, P(OCH₂)₃CC₂H₅, P(C₆H₅)₃, P(OC₂H₅)₃, P-n-Bu₃, P(C₆H₁₁)₃] is reported and the reduction mechanism is discussed. The dependence of the E_{$\text{1}\text{2}$} of thecomplexes on the properties of the ligands is analysed, and a linear plot of E_{$\text{1}\text{2}$} vs. ΔHNP of the ligands is observed. The pseudo first-order rate constants for the reduction of the complexes with NaBH₄ in ACN are reported.