Ru-MCM-41 catalysts were investigated in the diastereoselective hydrogenation of class F prostaglandin intermediates.
Ž The catalysts were prepared by deposition of Ru from different precursors ruthenium acetylacetonate, ruthenium chloride or . ruthenium hexaamine chloride . These catalysts were characterized using several techniques: atomic emission spectroscopy with inductively coupled plasma, N adsorption-desorption curves at 77 K, H -chemisorption, temperature-programmed 2 2 Ž . oxidation, temperature-programmed reduction, XPS, XRD and transmission electron microscopy TEM . The measurements indicated that Ru is homogeneously distributed on the surface of MCM-41 and that using the hexamine chloride complex allows a better penetration of Ru inside the mesoporous tubes then the other two precursors. Hydrogenation of a X Ž . prostaglandin F intermediate, namely the one with R s H and -R s CH -O-C H m Cl, showed that the catalysts 2 6 4
prepared using ruthenium acetylacetonate and ruthenium chloride exhibit a higher selectivity to allylic alcohol than that prepared using ruthenium hexaamine chloride. In all the investigated catalysts the diastereomeric excess was in the Ž . 11 R,15S allyl alcohol and it varied in the same order as the chemoselectivity. A positive effect of pressure was found.