ZIEGLER SYSTEMS AS HYDROGENATION CATALYSTS .2. DEPENDENCE OF THE HYDROGENATION ACTIVITY OF COBR2 LI[ALHN(O-R)4-N] SYSTEMS FROM THE CONCENTRATION OF THE REDUCING AGENT/

The hydrogenation activity of Li[AlHn(O-R)4-n]/CoBr2 systems in THF de pends on the number of H atoms n and on the R group of the reducing ag ent. The change of activity with increasing concentration of the alkox yalanate can be described as a 1: 1 equilibrium between the catalyst a nd the reducing agent, when n = 1 and R = t-butyl. In all other cases the range of activity is very small and can be described as the stepwi se formation of a bis-adduct.