Tricarbonyl(h6-Arene)Chromium(0) Complexes as Chiral Auxiliaries: Asymmetric Synthesis of b-Lactones

Abstract

The optically pure tricarbonyl(h6-2-substituted benzaldehydes)chromium are used as chiral auxiliaries in the condensation with a series of doubly lithiated carboxylic acids. The intramolecular ring closure of the obtained Cr(CO)3 complexed b-hydroxyacids affords the optically pure b-lactones in satisfactory yield.

Keywords

• b-lactones
• stereoselective synthesis
• 2-oxetanones
• chromiumtricarbonyl benzaldehydes