Diastereoselective hydrogenation of a prostaglandinic intermediate over chirally modified Pt/Al2O3

Liquid phase diastereoselective hydrogenation of a prostaglandin-F intermed iate has been studied over two commercial 5% Pt/Al2O3 catalysts. More speci fically, the effect of metal dispersion and pore diameter on the reaction, as well as the conditions which allow to improve the diastereoselectivity a nd eventually orient towards the synthesis of the natural-like compound hav e been examined. The catalysts were characterized by nitrogen sorption isot herms, XRD, Hn-chemisorption, and XPS. It has been found that the character istics of the catalysts (especially the textural properties) and the nature of the solvent strongly influence the catalytic behavior. In the presence of acetic acid as a solvent, it is possible to direct the formation of ally lic alcohol to the (11S,15S) configuration which corresponds to the natural -like diastereoisomer compound. (C) 2000 Elsevier Science B.V. All rights r eserved.