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Development of (trimethylsilyl)ethyl ester protected enolates and applications in palladium-catalyzed enantioselective allylic alkylation: intermolecular cross-coupling of functionalized electrophiles.

ABSTRACT: The development of (trimethylsilyl)ethyl ester protected enolates is reported. The application of this class of compounds in palladium-catalyzed asymmetric allylic alkylation is explored, yielding a variety of ?-quaternary six- and seven-membered ketones and lactams. Independent coupling partner synthesis engenders enhanced allyl substrate scope relative to traditional ?-ketoester substrates; highly functionalized ?-quaternary ketones generated by the union of (trimethylsilyl)ethyl ?-ketoesters and sensitive allylic alkylation coupling partners serve to demonstrate the utility of this method for complex fragment coupling.

SUBMITTER: Reeves CM

PROVIDER: S-EPMC4011571 | biostudies-literature | 2014 May

REPOSITORIES: biostudies-literature

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Development of (trimethylsilyl)ethyl ester protected enolates and applications in palladium-catalyzed enantioselective allylic alkylation: intermolecular cross-coupling of functionalized electrophiles.

Reeves Corey M CM Behenna Douglas C DC Stoltz Brian M BM

Organic letters 20140411 9

The development of (trimethylsilyl)ethyl ester protected enolates is reported. The application of this class of compounds in palladium-catalyzed asymmetric allylic alkylation is explored, yielding a variety of α-quaternary six- and seven-membered ketones and lactams. Independent coupling partner synthesis engenders enhanced allyl substrate scope relative to traditional β-ketoester substrates; highly functionalized α-quaternary ketones generated by the union of (trimethylsilyl)ethyl β-ketoesters ...[more]

PMID: 24724872

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