Site-Specific Covalent Immobilization of a Racemization Catalyst onto Lipase-containing Beads
(English)Manuscript (preprint) (Other academic)
The synthesis and application of the novel heterogeneous bifunctional catalyst CALB-5 as a racemization and resolution catalyst for the dynamic kinetic resolution is described. The semisynthetic ruthenium lipase hybrid CALB-5 was obtained by inhibiting CALB beads with the novel ruthenium phosphonate complex 5 possessing a lipase active site-directed phosphonate group. By partially inhibiting the lipase beads with 5, a bifunctional catalytic system was obtained. Racemization, by the Ru-catalytic site, gave 0% ee after 24 h, and the kinetic resolution, enzymatic acylation by the uninhibited CALB sites, gave 28% conversion of 1-phenylethanol after 3 h with >99% ee of the acetylated product. A dynamic kinetic resolution experiment of (S)-1-phenylethanol with CALB-5 gave the acylated (R)-product in 18% yield and with >99% ee.
Research subject Organic Chemistry
IdentifiersURN: urn:nbn:se:su:diva-31311OAI: oai:DiVA.org:su-31311DiVA: diva2:276051