[(eta(5)-C5R5)Ru(N-N*)(NCMe)]PF6 (R=H, N-N*=(Sa)-1, 5; (Sa)-2, 6; (R,R)-3, 7; (R,R)-4; 8; R=Me, N-N* =(Sa)-1, 9) complexes containing N-N* bulky chiral ligands of different rigidity and flexibility were synthesized by reacting the precursor [(eta(C5Me5)-C-5)Ru(NCMe)(3)]PF6 (R=H, Me) with the N-N* ligand in a 1:1 molar ratio. The more bulky (eta(5)-C5Me5) ligand gave low stability to the complexes [(eta(C5Me5)-C-5)Ru(N-N*)(NCMe)]PF6, when N-N*=(Sa)-2, (R,R)-3, (R,R)-4, in comparison to (eta(5)-C5R5) ligand and prevented their characterization. The catalytic activity of complexes 5-9 in allylic alkylation and etherifications reactions, using malonate and phenoxide anions as nucleophiles respectively, were investigated and compared to the results obtained with corresponding precursors [(eta(5)-C5R5)Ru(NCMe)]PF6 and [(eta(C5Me5)-C-5)Ru(NCMe)(3)]PF6. The effect of bulkiness and of rigidity and flexibility ligand features is discussed. (C) 2009 Elsevier B.V. All rights reserved.