Lipase Immobilized on MCFs as Biocatalysts for Kinetic and Dynamic Kinetic Resolution of <i>sec</i>-Alcohols

• Main Authors: Dominika Stradomska, Monika Heba, Aleksandra Czernek, Nikodem Kuźnik, Danuta Gillner, Katarzyna Maresz, Wojciech Pudło, Andrzej Jarzębski, Katarzyna Szymańska
• Format: Article
• Language: English
• Published: MDPI AG 2021-04-01
• Series: Catalysts
• Subjects: chiral secondary alcohols; resolution of enantiomers; dynamic kinetic resolution; DKR; synthesis of enantiomers; bicatalytic tandem
• Online Access: https://www.mdpi.com/2073-4344/11/4/518

Dynamic kinetic resolution (DKR) is one of the most attractive methods for enantioselective synthesis. In the reported studies, lipase B from<i> Candida antarctica</i> (CALB) immobilized on siliceous mesoporous cellular foams (MCF) functionalized with different hydrophobic groups, and two ruthenium complexes with substituted cyclopentadienyl ligands were investigated as catalysts for the chemoenzymatic DKR of (<i>rac</i>)-1-phenylethanol, using Novozym 435 as a benchmark biocatalyst. Studies on the (<i>rac</i>)-1-phenylethanol transesterification reaction showed that CALB supported on MCFs grafted with methyl groups is a promising biocatalyst and isopropenyl acetate is a preferable acylation agent. Both Ru-complexes activated by K₃PO₄ or <i>t-</i>BuOK, proved to be effective catalysts of the racemization reaction. The final DKR experiments using all catalysts combinations singled out, gave 96% conversion, and (<i>R</i>)-1-phenylethyl acetate enantiomeric excess of 98% in 8 h using K₃PO₄ activator.