Dynamic kinetic resolution of γ-hydroxy acid derivatives

Enzymatic resolution and dynamic kinetic resolution of γ-hydroxy acid derivatives 1 have been investigated. Efficient kinetic resolution was obtained using Pseudomonas cepacia lipase in toluene (E value ∼400). The combination of enzymatic kinetic resolution with a ruthenium-catalyzed racemization resulted in an efficient dynamic kinetic resolution. The use of a hydrogen source to depress ketone formation in the dynamic kinetic resolution yields the corresponding acetates in good yield (up to 93%) and enantioselectivity (up to 99%).