3654.     WENDER, I., ORCHIN, M., AND STORCH, H. H.  Mechanism of the Oxo and Related Reactions.  III.  Evidence for Homogeneous Hydrogenation.  Jour. Am. Chem. Soc., vol. 72, 1950, pp. 4842-4843.

        It has been shown that the hydroformylation reaction is often accompanied by hydrogenation; indeed, in some instances, hydrogenation proceeds to the exclusion of hydroformylation.  Evidence is presented that strongly indicates that the great variety of hydrogenations that occur in the presence of Co and a high partial pressure of CO probably proceeded by homogeneous catalysis in which [Co(CO)4]2 or HCo(CO)4 functions as the catalyst.