The present paper reports the ROMP of norbornene with [RuCl 2 (PPh 3 ) 2 (L) x ], where L represents the acyclic amines diethanolamine, triethanolamine, triethylamine, phenylamine, diphenylamine or sec-butylamine. Previous representative results with cyclic amines are also cited to observe of the behavior of cyclic and acyclic amines as ancillary ligands. Three productive types of ligands were observed as a function of their electronic nature and steric hindrance: ligands with high cone angle and strong σ-donor character (NH 2 s Bu, NEt 3 and piperidine), ligands with high cone angle and low σ-donor character (NH 2 Ph and NHPh 2 ) and ligand with low cone angle and π-acceptor character (4-H 2 NC(O)-pyridine). Ligands with low cone angle and strong σ-donor character can restrict the catalytic activity of the metal complex (imidazole, pyridine, 4-H 3 C-pyridine and 4-H 2 N-pyridine). Thus, latent complexes can be designed using different amines as ancillary ligands.