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Anion-Abstraction Catalysis: The Cooperative Mechanism of ?-Chloroether Activation by Dual Hydrogen-Bond Donors.

ABSTRACT: We provide here a detailed mechanistic characterization of the electrophile-activation step in a representative thiourea-catalyzed enantioselective reaction proposed to involve generation of ion-pair intermediates. Comparison of catalyst-promoted substrate epimerization with catalytic alkylation points to the participation of a common intermediate in both pathways and provides conclusive evidence for anion abstraction via an SN1-like pathway involving the cooperative action of two catalyst molecules.

SUBMITTER: Ford DD

PROVIDER: S-EPMC6870875 | biostudies-literature | 2016 Jul

REPOSITORIES: biostudies-literature

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Anion-Abstraction Catalysis: The Cooperative Mechanism of α-Chloroether Activation by Dual Hydrogen-Bond Donors.

Ford David D DD Lehnherr Dan D Kennedy C Rose CR Jacobsen Eric N EN

ACS catalysis 20160610 7

We provide here a detailed mechanistic characterization of the electrophile-activation step in a representative thiourea-catalyzed enantioselective reaction proposed to involve generation of ion-pair intermediates. Comparison of catalyst-promoted substrate epimerization with catalytic alkylation points to the participation of a common intermediate in both pathways and provides conclusive evidence for anion abstraction via an SN1-like pathway involving the cooperative action of two catalyst molec ...[more]

PMID: 31754547

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