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Zirconocene-Mediated Carbonylative Coupling of Grignard Reagents.

ABSTRACT: Organozirconocenes are versatile synthetic intermediates that can undergo carbonylation to yield acyl anion equivalents. Zirconocene hydrochloride ([Cp2 ZrHCl]) is often the reagent of choice for accessing these intermediates but generates organozirconocenes only from alkenes and alkynes. This requirement eliminates a broad range of substrates. For example, organozirconocenes in which the zirconium center is bonded to an aromatic ring, a benzylic group, or an alkyl group that possesses a tertiary or quaternary carbon atom ? to the carbon-zirconium bond can not be formed in this way. To provide more generalized access to acyl zirconium reagents, we explored the transmetalation of Grignard reagents with zirconocene dichloride under a CO atmosphere. This protocol generates acyl zirconium(IV) complexes that are inaccessible with the Schwartz reagent, including those derived from secondary and tertiary alkyl and aryl Grignard reagents.

SUBMITTER: Moss M

PROVIDER: S-EPMC4980256 | biostudies-literature | 2016 Aug

REPOSITORIES: biostudies-literature

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Zirconocene-Mediated Carbonylative Coupling of Grignard Reagents.

Moss Melissa M Han Xinping X Ready Joseph M JM

Angewandte Chemie (International ed. in English) 20160713 34

Organozirconocenes are versatile synthetic intermediates that can undergo carbonylation to yield acyl anion equivalents. Zirconocene hydrochloride ([Cp2 ZrHCl]) is often the reagent of choice for accessing these intermediates but generates organozirconocenes only from alkenes and alkynes. This requirement eliminates a broad range of substrates. For example, organozirconocenes in which the zirconium center is bonded to an aromatic ring, a benzylic group, or an alkyl group that possesses a tertiar ...[more]

PMID: 27410720

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