New chloramphenicol Schiff base ligands for the titanium-mediated asymmetric aldol reaction of α,β-unsaturated aldehydes with diketene: a short synthesis of atorvastatin calcium†
Abstract
Several novel chiral Schiff base ligands were prepared from a commercially available chloramphenicol base and applied to the titanium-mediated asymmetric aldol reaction of diketene with various α,β-unsaturated aldehydes. This reaction proceeded in good yield with high enantioselectivity. The synthetic utility of this methodology was demonstrated in the short synthesis of atorvastatin calcium.