Process for the preparation of trans-(R,R)-actinol

Abstract

A process for the manufacture of trans-(R,R)-actinol by diasteroselective transfer hydrogenation of levodione comprises hydrogenating (R)-levodione in the presence of a hydrogen donor, which simultaneously can be used as the solvent, and an amino-amide-ruthenium complex, especially of the formula RuH(L{—H})(Y), wherein Y signifies a neutral ligand and L signifies an optionally optically active monosulphonylated diamine ligand, as defined in more detail in the description. Moreover, the invention is concerned with some of the amino-amide-ruthenium complexes and with the corresponding precursors to these complexes, which have halogen in place of H. The product of the process in accordance with the invention, trans-(R,R)-actinol, is known as an important building block for the synthesis of carotenoids, e.g. zeaxanthin. By the process trans-(R,R)-actinol is made available in particularly high enantiomeric and diasteromeric purity.

Dependencies are inferred from the claim text.