A method for preparing an enantiomeric chromane, by asymmetrically
hydrogenating a chromene compound in the presence of an Ir catalyst
having a chiral ligand. The method includes the enantioselective
preparation of enantiomeric equol. A preferred Ir catalyst has a chiral
phosphineoxazoline ligand. Enantiomeric chromanes of high stereoselective
purity can be obtained.