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Palladium-Catalyzed Enantioselective Decarboxylative Allylic Alkylation of Cyclopentanones.

ABSTRACT: The first general method for the enantioselective construction of all-carbon quaternary centers on cyclopentanones by enantioselective palladium-catalyzed decarboxylative allylic alkylation is described. Employing the electronically modified (S)-(p-CF3)3-t-BuPHOX ligand, ?-quaternary cyclopentanones were isolated in yields up to >99% with ee's up to 94%. Additionally, in order to facilitate large-scale application of this method, a low catalyst loading protocol was employed, using as little as 0.15 mol % Pd, furnishing the product without any loss in ee.

SUBMITTER: Craig RA

PROVIDER: S-EPMC4640231 | biostudies-literature | 2015 Nov

REPOSITORIES: biostudies-literature

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Palladium-Catalyzed Enantioselective Decarboxylative Allylic Alkylation of Cyclopentanones.

Craig Robert A RA Loskot Steven A SA Mohr Justin T JT Behenna Douglas C DC Harned Andrew M AM Stoltz Brian M BM

Organic letters 20151026 21

The first general method for the enantioselective construction of all-carbon quaternary centers on cyclopentanones by enantioselective palladium-catalyzed decarboxylative allylic alkylation is described. Employing the electronically modified (S)-(p-CF3)3-t-BuPHOX ligand, α-quaternary cyclopentanones were isolated in yields up to >99% with ee's up to 94%. Additionally, in order to facilitate large-scale application of this method, a low catalyst loading protocol was employed, using as little as 0 ...[more]

PMID: 26501770

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