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Palladium-catalyzed ?,?-dehydrogenation of acyclic ester equivalents promoted by a novel electron deficient phosphinooxazoline ligand.

ABSTRACT: A unique example of Pd-catalyzed decarboxylative dehydrogenation of fully substituted N-acyl allyl enol carbonates is enabled by a new electron deficient phosphinooxazoline (PHOX) ligand. The reaction proceeds from the Z-enol carbonate to provide dehydrogenation products exclusively in high E/Z selectivity, while the E-enol carbonate provides the ?-allylation product with only minor dehydrogenation. The reaction proceeds with a broad scope of (Z)-enol carbonates derived from N-acyl indoles to furnish acyclic formal ?,?-unsaturated ester equivalents.

SUBMITTER: Fulton TJ

PROVIDER: S-EPMC7119178 | biostudies-literature | 2019 Aug

REPOSITORIES: biostudies-literature

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Palladium-catalyzed α,β-dehydrogenation of acyclic ester equivalents promoted by a novel electron deficient phosphinooxazoline ligand.

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

Tetrahedron 20190601 31

A unique example of Pd-catalyzed decarboxylative dehydrogenation of fully substituted N-acyl allyl enol carbonates is enabled by a new electron deficient phosphinooxazoline (PHOX) ligand. The reaction proceeds from the Z-enol carbonate to provide dehydrogenation products exclusively in high E/Z selectivity, while the E-enol carbonate provides the α-allylation product with only minor dehydrogenation. The reaction proceeds with a broad scope of (Z)-enol carbonate ...[more]

PMID: 32255844

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