The Application of Two-Phase Catalytic System in Enantioselective Separation of Racemic (R,S)-1-Phenylethanol

Abstract

Kinetic resolution is one of the methods which allows obtaining enantiomerically pure compounds. In the study presented herein, enantioselective biotransformations of (R,S)-1-phenylethanol were performed with the use of various catalytic systems containing ionic liquids and n-heptane or toluene as a reaction medium, vinyl acetate or isopropenyl acetate as an acetylating agent, and lipases from Burkholderia cepacia or Candida rugosa. The conducted studies proved that the use of Burkholderia cepacia lipase, vinyl acetate, and n-heptane with [EMIM][BF4] allows obtaining enantiomerically pure 1-phenylethyl acetate, with the enantiomeric excess of products eep = 98.9%, conversion c = 40.1%, and high value of enantioselectivity E > 200. Additionally, the use of ionic liquids allowed us to reuse enzyme in 5 reaction cycles, ensuring the high operational stability of the protein.