Synthesis of C2-symmetrical bis-β-amino alcohols and their application in the enantioselective addition of diethylzinc to aldehydes

The C2-symmetrical bis-β-amino alcohols 1–6 were prepared and especially attention is focused on bridges, which link the two β-amino alcohol units. These ligands have been applied as chiral catalysts in the asymmetric addition of diethylzinc to aldehydes. sec-Alcohols have been obtained in good yields with up to 95.4% enantiomeric excess.