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Palladium-Catalyzed Annulations of Strained Cyclic Allenes.

ABSTRACT: We report Pd-catalyzed annulations of in situ generated strained cyclic allenes. This methodology employs aryl halides and cyclic allene precursors as the reaction partners in order to generate fused heterocyclic products. The annulation proceeds via the formation of two new bonds and an sp³ center. Moreover, both diastereo- and enantioselective variants of this methodology are validated, with the latter ultimately enabling the rapid enantioselective synthesis of a complex hexacyclic product. Studies leveraging transition metal catalysis to intercept cyclic allenes represent a departure from the more common, historical modes of cyclic allene trapping that rely on nucleophiles or cycloaddition partners. As such, this study is expected to fuel the development of reactions that strategically merge transition metal catalysis and transient strained intermediate chemistry for the synthesis of complex scaffolds.

SUBMITTER: Kelleghan AV

PROVIDER: S-EPMC8290222 | biostudies-literature | 2021 Jun

REPOSITORIES: biostudies-literature

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Palladium-Catalyzed Annulations of Strained Cyclic Allenes.

Kelleghan Andrew V AV Witkowski Dominick C DC McVeigh Matthew S MS Garg Neil K NK

Journal of the American Chemical Society 20210618 25

We report Pd-catalyzed annulations of in situ generated strained cyclic allenes. This methodology employs aryl halides and cyclic allene precursors as the reaction partners in order to generate fused heterocyclic products. The annulation proceeds via the formation of two new bonds and an sp<sup>3</sup> center. Moreover, both diastereo- and enantioselective variants of this methodology are validated, with the latter ultimately enabling the rapid enantioselective synthesis of a complex hexacyclic ...[more]

PMID: 34143634

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