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Propargyltrimethylsilanes as allene equivalents in transition metal-catalyzed [5 + 2] cycloadditions.

ABSTRACT: Conventional allenes have not been effective ?-reactive 2-carbon components in many intermolecular cycloadditions including metal-catalyzed [5 + 2] cycloadditions. We report herein that rhodium-catalyzed [5 + 2] cycloadditions of propargyltrimethylsilanes and vinylcyclopropanes provide, after in situ protodesilylation, a highly efficient route to formal allene cycloadducts. Propargyltrimethylsilanes function as safe, easily handled synthetic equivalents of gaseous allenes and hard-to-access monosubstituted allenes. In this one-flask procedure, they provide cycloadducts of what is formally addition to the more sterically encumbered allene double bond.

SUBMITTER: Wender PA

PROVIDER: S-EPMC4051429 | biostudies-literature | 2014 Jun

REPOSITORIES: biostudies-literature

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Propargyltrimethylsilanes as allene equivalents in transition metal-catalyzed [5 + 2] cycloadditions.

Wender Paul A PA Inagaki Fuyuhiko F Pfaffenbach Magnus M Stevens Matthew C MC

Organic letters 20140512 11

Conventional allenes have not been effective π-reactive 2-carbon components in many intermolecular cycloadditions including metal-catalyzed [5 + 2] cycloadditions. We report herein that rhodium-catalyzed [5 + 2] cycloadditions of propargyltrimethylsilanes and vinylcyclopropanes provide, after in situ protodesilylation, a highly efficient route to formal allene cycloadducts. Propargyltrimethylsilanes function as safe, easily handled synthetic equivalents of gaseous allenes and hard-to-access mono ...[more]

PMID: 24819093

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