title: Kinetic resolution and chemoenzymatic dynamic kinetic resolution of functionalized gamma-hydroxy amides.
abstract: [reaction: see text] An efficient kinetic resolution of racemic gamma-hydroxy amides 1 was performed via Pseudomas cepacia lipase (PS-C)-catalyzed transesterification. The enzyme PS-C tolerates both variation in the chain length and different functionalities giving good to high enantioselectivity (E values of up to >250). The combination of enzymatic kinetic resolution with a ruthenium-catalyzed racemization led to a dynamic kinetic resolution. The use of 2,4-dimethyl-3-pentanol as a hydrogen source to suppress ketone formation in the dynamic kinetic resolution yields the corresponding acetates in good yield and good to high enantioselectivity (ee's up to 98%). The synthetic utility of this procedure was illustrated by the practical synthesis of the versatile intermediate gamma-lactone (R)-5-methyltetrahydrofuran-2-one.
authors.affiliation: Department of Organic Chemistry, Arrhenius Laboratory, Stockholm University, SE-10691 Stockholm, Sweden.
authors.forename: Ann-Britt L
authors.initials: AB
authors.lastname: Fransson
authors.forename: Linnéa
authors.initials: L
authors.lastname: Borén
authors.forename: Oscar
authors.initials: O
authors.lastname: Pàmies
authors.forename: Jan-E
authors.initials: JE
authors.lastname: Bäckvall