Novel highly modular C2-symmetric oxazoline ligands—application in titanium-catalyzed diethylzinc additions to aldehydes

Novel C2-symmetric tetradentate bis-oxazoline ligands were efficiently prepared from α-amino acids, 1,2-amino alcohols and 1,2- or 1,3-diacids. The ligands were employed in the titanium-catalyzed addition of diethylzinc to benzaldehyde, and depending on conditions used, moderate to high enantioselectivities of the formed 1-phenylpropanol were obtained.