Substituent Effect on the Absolute Stereochemistry of the Asymmetric Reduction of Fluorine-Containing β-Diketones by Bakers' Yeast

Abstract

Fluorine-containing β-diketones (la-d) were reduced by free bakers' yeast (FBY) and immobilized baker yeast (IMBY) in water, to give optically-active fluorinated β-hydroxyketones (2a-d). It was found that the reaction is highly regioselective, and that the stereochemistry of the reduction is controlled by the R substituent.

Key Words:

• Bakers' yeast reduction
• chiral fluorinated β-hydroxyketones
• absolute configuration