Hydrogenation of non-activated alkenes catalysed by water-soluble ruthenium carbonyl clusters using a biphasic protocol

The use of the water soluble ruthenium clusters Ru₃(CO)_12−x(TPPTN)_x (x=1 1, 2 2 or 3 3) and H₄Ru₄(CO)₁₁(TPPTN) 4 (TPPTN=P{m-C₆H₄SO₃Na)₃) as catalyst precursors in the hydrogenation of non-activated alkenes under biphasic conditions is described. Each cluster displays activity under moderate conditions, ca. 60 atm. H₂ at 60°C, with catalytic turnovers up to ca. 500. The trinuclear clusters undergo transformation during reaction but can be reused repeatedly without loss of activity. Other methodologies such as ionic liquid–organic and the use of silica supports have been attempted with these clusters but they are less effective than the aqueous–organic regime.