Preparation and Reactivity of Mixed-Ligands Hydride Complexes [RuHCl(CO)(PPh 3 ) 2 P(OR) 3 ]

Mixed-ligands hydride complexes [RuHCl(CO)(PPh 3 ) 2 P(OR) 3 ] (2) (R = Me, Et) were prepared by allowing [RuHCl(CO)(PPh 3 ) 3 ] (1) to react with an excess of phosphites P(OR) 3 in refluxing benzene. Treatment of hydrides 2 first with triflic acid and next with an excess of hydrazine afforded hydrazine complexes [RuCl(CO)(κ 1 -NH 2 NHR1)(PPh 3 ) 2 P(OR) 3 ]BPh 4 (3, 4) (R1 = H, CH 3 ). Diethylcyanamide derivatives [RuCl(CO)(N≡CNEt 2 )(PPh 3 ) 2 P(OR) 3 ]BPh 4 (5) were also prepared by reacting 2 first with HOTf and then with N≡CNEt 2 . The complexes were characterized spectroscopically and by X-ray crystal structure determination of [RuHCl(CO)(PPh 3 ) 2 P(OEt) 3 ] (2b).