Abstract: This invention concerns the use of M[BR.sub.3 H].sub.y reagents for activating or regenerating deactivated or degraded Ni catalyst used in Ni-catalyzed alkene hydrocyanation processes in the presence of an organic phosphorus compound, where M is an electropositive ion excluding nickel, such as, but not limited to, the Group 1A cations, the Group IIA cations, the lanthanide cations and the quaternary ammoniums and R is an organic radical of up to 18 carbon atoms, and where y is equal to the net charge of the cation. The invention also concerns a process for activation or regeneration of Ni-catalysts using MH and a catalytic amount of BR.sub.3.

Abstract: Process of polyene hydrocyanation, in particular diene hydrocyanation, wherein a promotionally effective amount of any acid with a pK.sub.a above about 2 and below and 14, preferably aryl alcohols such as phenol and cresols, is used.