Facile Synthesis of C3-Symmetric Tripodal β-Hydroxy Amide Ligands and Their Ti (IV) Complex-Catalyzed Asymmetric Addition of Diethylzinc to Aldehydes

Chiral C3-symmetric tripodal tris(β-hydroxy amide) ligands have been conveniently synthesized via the reaction of 1,3,5-benzenetricarboxylic chloride and chiral amino alcohols, and the corresponding tris(amino alcohol) ligands were obtained via the borane reduction of amides. The asymmetric diethylzinc addition to various aldehydes catalyzed by these chiral ligand-Ti (IV) complexes gave modest enantioselectivities.