One-Pot Synthesis of Enantiopure 3,4-Dihydroisocoumarins through Dynamic Reductive Kinetic Resolution Processes
journal contributionposted on 02.08.2013, 00:00 by Juan Mangas-Sánchez, Eduardo Busto, Vicente Gotor, Vicente Gotor-Fernández
A straightforward chemoenzymatic synthesis of enantiopure 4-alkyl-3-methyl-3,4-dihydroisocoumarins through a ketoreductase-catalyzed one-pot dynamic reductive kinetic resolution is reported. E. coli/ADH-A cells have shown outstanding diastereo- and enantioselectivity toward the bioreduction of a series of racemic ketones, with the use of anion exchange resins or triethylamine being compatible in the same aqueous reaction medium. The so-obtained enantiopure alcohols were subsequently cyclized in acid media affording the corresponding lactones in good to excellent conversions (72–96%) and excellent selectivities (dr ≥99:1 and ee >99%).