Ruthenium Phosphine/Diimine Complexes: Syntheses, Characterization, Reactivity with Carbon Monoxide, and Catalytic Hydrogenation of Ketones †

The cis-[RuCl2(PPh3)2(N−N)] (N−N = bipy (1), Me-bipy (2), phen (3), and bathophen (4)) complexes were used to synthesize five new electron-rich phosphine-containing complexes cis-[RuCl2(dcype)(N−N)] (N−N = bipy (1a), Me-bipy (2a), phen (3a), and bathophen (4a)) and cis-[RuCl2(PEt3)2(bipy)] (1c) by phosphine exchange. These complexes were obtained and characterized by NMR (31P{1H}, 1H), cyclic voltammetry, and elemental analysis. Electrochemical studies of these complexes reveal a single reduction process (RuIII/RuII). These complexes are more easily oxidized than their analogues cis-[RuCl2(dppb)(N−N)]. The reactivity of complexes cis-[RuCl2(dcype)(N−N)] with carbon monoxide was tested, and dissociation of one chloride was observed, leading to the formation of four new cationic species with general formula [RuCl(CO)(dcype)(N−N)](PF6) (bipy (1b), Me-bipy (2b), phen (3b), and bathophen (4b)). The complexes described here and elsewhere with general formulas cis-[RuCl2(P−P)(N−N)], [RuCl(CO)(dcype)(N−N)](PF6), ...