The hydrogenation of cis-2-pentenenitrile (C2PN) has been studied over Ni/alumina. Hydrogenation to n-pentanenitrile (PN) and subsequent isomerisation to trans-2-pentenenitrile (T2PN) and trans-3-pentenenitrile (T3PN) was observed. 1-Pentanamine (PA) was also detected in the initial stages of the catalyst life. Use of selective poisoning of metal sites with carbon monoxide and acid sites with ammonia revealed that hydrogenation was a function of the metal, while isomerisation was solely a function of the support. I-Pentanamine was produced by the support but the site was rapidly deactivated due to carbon laydown. (c) 2006 Elsevier B.V. All rights reserved.