New Proline–Oxazoline Ligands and Their Application in the Asymmetric Nozaki–Hiyama–Kishi Reaction

Abstract

Abstract Sixteen members of a new ligand class incorporating an oxazoline ring linked by an amide bond to a chiral protected proline unit were prepared in a high‐yielding four‐step synthesis from readily available chiral amino alcohols and N ‐protected proline. The ligands were applied in the enantioselective Nozaki–Hiyama–Kishi allylation of benzaldehyde and gave enantioselectivities of up to 57 %. Diastereomeric ligand pairs were prepared to determine the role of each chiral centre in enantioselection.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)