Synfacts 2007(3): 0294-0294  
DOI: 10.1055/s-2007-968247
Metal-Catalyzed Asymmetric Synthesis and Stereoselective Reactions
© Georg Thieme Verlag Stuttgart · New York

Hydroxylation of Oxindoles and β-Keto Esters Using DBFOX Ligand

Contributor(s): Hisashi Yamamoto, Matthew B. Boxer
T. Ishimaru, N. Shibata*, J. Nagai, S. Nakamura, T. Toru*, S. Kanemasa
Nagoya Institute of Technology and Kyushu University, Kasuga, Japan
Further Information

Publication History

Publication Date:
20 February 2007 (online)

Significance

The enantioselective synthesis of 3-aryl- and 3-alkyl-3-hydroxy-2-oxindoles is described. Oxidation with the racemic oxidant 1 gave the best results when employing Zn(II)-­DBFOX as catalyst. 3-Aryl-substituted 2-oxindoles gave the highest ee values, while the 3-alkyl derivates gave ee values >80% with reasonable yields. Use of this oxidation system with Ni(II)-DBFOX succeeded in the asymmetric oxidation of β-keto esters.