Effects of organic solvents and ionic liquids on the aminolysis of (RS)-methyl mandelate catalyzed by lipases

The enzymatic resolution of (RS)-methyl mandelate with n-butylamine using lipases in organic solvents (n-hexane, tert-butanol, and chloroform) and ionic liquids [BMIm][BF4] and [BMIm][PF6] is reported. The amide configuration is dependent on the organic solvent. When using mixtures of chloroform or tert-butanol/ionic liquids (10:1 v/v) with CAL-B as the catalyst, the amides were obtained in high enantiomeric excess (eep >99% and E >200).

Solvents: n-hexane, chloroform, tert-butanol, [BMIm][BF4], [BMIm][PF6]; eep = 10 >99%; ees = 2–95%; E = 2 >200%.Figure optionsDownload as PowerPoint slide