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Biocatalytic Conversion of Cyclic Ketones Bearing ?-Quaternary Stereocenters into Lactones in an Enantioselective Radical Approach to Medium-Sized Carbocycles.

ABSTRACT: Cyclic ketones bearing ?-quaternary stereocenters underwent efficient kinetic resolution using cyclohexanone monooxygenase (CHMO) from Acinetobacter calcoaceticus. Lactones possessing tetrasubstituted stereocenters were obtained with high enantioselectivity (up to >99?%?ee) and complete chemoselectivity. Preparative-scale biotransformations were exploited in conjunction with a SmI2 -mediated cyclization process to access complex, enantiomerically enriched cycloheptan- and cycloctan-1,4-diols. In a parallel approach to structurally distinct products, enantiomerically enriched ketones from the resolution with an ?-quaternary stereocenter were used in a SmI2 -mediated cyclization process to give cyclobutanol products (up to >99?%?ee).

SUBMITTER: Morrill C

PROVIDER: S-EPMC6055628 | biostudies-literature | 2018 Mar

REPOSITORIES: biostudies-literature

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