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Palladium-Catalyzed trans-Hydroalkoxylation: Counterintuitive Use of an Aryl Iodide Additive to Promote C-H Bond Formation.

ABSTRACT: We report an enantioselective palladium-catalyzed trans-hydroalkoxylation of propargylic amines with a trifluoroacetaldehyde-derived tether to build chiral oxazolidines. Diastereoselective hydrogenation using a heterogeneous palladium catalyst then gave access to protected benzylic amino alcohols in 45-87% yields and 84-94% ee values. Hydroalkoxylation of the alkynes required a catalytic amount of aryl iodide, highlighting the counterintuitive key role played by a putative Pd(II)/ArI oxidative addition complex to promote oxypalladation/protodemetalation.

SUBMITTER: Das A

PROVIDER: S-EPMC9251722 | biostudies-literature | 2022 Jul

REPOSITORIES: biostudies-literature

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Palladium-Catalyzed <i>trans</i>-Hydroalkoxylation: Counterintuitive Use of an Aryl Iodide Additive to Promote C-H Bond Formation.

Das Ashis A Buzzetti Luca L Puriņš Mikus M Waser Jerome J

ACS catalysis 20220613 13

We report an enantioselective palladium-catalyzed <i>trans</i>-hydroalkoxylation of propargylic amines with a trifluoroacetaldehyde-derived tether to build chiral oxazolidines. Diastereoselective hydrogenation using a heterogeneous palladium catalyst then gave access to protected benzylic amino alcohols in 45-87% yields and 84-94% ee values. Hydroalkoxylation of the alkynes required a catalytic amount of aryl iodide, highlighting the counterintuitive key role played by a putative Pd(II)/ArI oxid ...[more]

PMID: 35799768

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