Asymmetric Induction From Ethyl Lactate in the Reduction of Acetophenone to Phenylethanol

Abstract

Ethyl lactate was used for the first time as a solvent for acetophenone reduction to phenylethanol by borane and sodium tetrahydridoborate. Moderate enantiomeric excess was obtained with the pure reducing agents that could be improved up to 46% by employing stoichiometric amounts of the Lewis acid ZnCl₂. These are the highest e.e. values published for solvent‐induced chiral synthesis.

Keywords:

• Boron hydride
• phenylethanol
• reduction
• sodium tetrahydridoborate
• solvent‐induced chirality