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Ligand controlled highly regio- and enantioselective synthesis of alpha-acyloxyketones by palladium-catalyzed allylic alkylation of 1,2-enediol carbonates.

ABSTRACT: The palladium catalyzed decarboxylative asymmetric allylic alkylation of allyl 1,2-enediol carbonates 1 can decompose to either alpha-hydroxyketones 3 or alpha-hydroxyaldehydes 4. The product distribution is largely controlled by the ligand. Using Lnaph in DME we exclusively obtained the ketone product in good to excellent yields and high enantiomeric excesses. The reaction proceeds under extremely mild conditions, so we can have a broad range of choices of OR. Besides the commonly used protection groups such as OAc and OPiv, a more functionalized group such as methyl but-2-enoyl group can also be used, downstream process of which can afford other synthetically interesting structures.

SUBMITTER: Trost BM

PROVIDER: S-EPMC2711528 | biostudies-literature | 2008 Sep

REPOSITORIES: biostudies-literature

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Ligand controlled highly regio- and enantioselective synthesis of alpha-acyloxyketones by palladium-catalyzed allylic alkylation of 1,2-enediol carbonates.

Trost Barry M BM Xu Jiayi J Schmidt Thomas T

Journal of the American Chemical Society 20080819 36

The palladium catalyzed decarboxylative asymmetric allylic alkylation of allyl 1,2-enediol carbonates 1 can decompose to either alpha-hydroxyketones 3 or alpha-hydroxyaldehydes 4. The product distribution is largely controlled by the ligand. Using Lnaph in DME we exclusively obtained the ketone product in good to excellent yields and high enantiomeric excesses. The reaction proceeds under extremely mild conditions, so we can have a broad range of choices of OR. Besides the commonly used protecti ...[more]

PMID: 18710230

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