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Palladium-catalyzed enantioselective decarboxylative allylic alkylation of fully substituted N-acyl indole-derived enol carbonates.

ABSTRACT: The first enantioselective palladium-catalyzed decarboxylative allylic alkylation of fully substituted N-acyl indole-derived enol carbonates forming acyclic all-carbon quaternary stereocenters is reported. Excellent yields up to 99% and enantioselectivities up to 98% ee are obtained through the use of a new electron-deficient phosphinoxazoline (PHOX) ligand. Control of substrate enolate geometry is crucial for high selectivity. The obtained ?-quaternary N-acyl indoles are formal ester equivalents, and represent a useful handle for further synthetic transformations.

SUBMITTER: Alexy EJ

PROVIDER: S-EPMC6566452 | biostudies-literature | 2019 Jun

REPOSITORIES: biostudies-literature

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Palladium-catalyzed enantioselective decarboxylative allylic alkylation of fully substituted N-acyl indole-derived enol carbonates.

Alexy Eric J EJ Fulton Tyler J TJ Zhang Haiming H Stoltz Brian M BM

Chemical science 20190517 23

The first enantioselective palladium-catalyzed decarboxylative allylic alkylation of fully substituted N-acyl indole-derived enol carbonates forming acyclic all-carbon quaternary stereocenters is reported. Excellent yields up to 99% and enantioselectivities up to 98% ee are obtained through the use of a new electron-deficient phosphinoxazoline (PHOX) ligand. Control of substrate enolate geometry is crucial for high selectivity. The obtained α-quaternary N-acyl indoles are formal es ...[more]

PMID: 31360407

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