Direct n-octanol amination by ammonia on supported Ni and Pd catalysts: activity is enhanced by “spectator” ammonia adsorbates

Abstract

The direct amination of alcohols by ammonia is a promising sustainable route to primary amines. The development of novel heterogeneous catalysts calls for a better understanding of this reaction. Through a combination of well-designed catalytic tests and periodic DFT computations, we provide here a deeper understanding of the factors determining the activity of Ni and Pd catalysts. In particular, we demonstrate that a proper assessment of the relative activity requires the inclusion of a spectator species, namely ammonia, which modifies the rate limiting intermediate and transition state and thus affects the overall predicted activity. This better understanding paves the road for a rational improvement of metal-based catalysts.