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Palladium-catalyzed enantioselective Heck alkenylation of acyclic alkenols using a redox-relay strategy.

ABSTRACT: We report a highly enantioselective intermolecular Heck reaction of alkenyl triflates and acyclic primary or racemic secondary alkenols. The mild reaction conditions permit installation of a wide range of alkenyl groups at positions ?, ?, or ? to a carbonyl group in high enantioselectivity. The success of this reaction is attributed to the use of electron-withdrawing alkenyl triflates, which offer selective ?-hydride elimination followed by migration of the catalyst through the alkyl chain to give the alkenylated carbonyl products. The synthetic utility of the process is demonstrated by a two-step modification of a reaction product to yield a tricyclic core structure, present in various natural products.

SUBMITTER: Patel HH

PROVIDER: S-EPMC4785804 | biostudies-literature | 2015 Mar

REPOSITORIES: biostudies-literature

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Palladium-catalyzed enantioselective Heck alkenylation of acyclic alkenols using a redox-relay strategy.

Patel Harshkumar H HH Sigman Matthew S MS

Journal of the American Chemical Society 20150309 10

We report a highly enantioselective intermolecular Heck reaction of alkenyl triflates and acyclic primary or racemic secondary alkenols. The mild reaction conditions permit installation of a wide range of alkenyl groups at positions β, γ, or δ to a carbonyl group in high enantioselectivity. The success of this reaction is attributed to the use of electron-withdrawing alkenyl triflates, which offer selective β-hydride elimination followed by migration of the catalyst through the alkyl chain to gi ...[more]

PMID: 25738548

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