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DFT Studies on the Mechanism of the Iridium-Catalyzed Formal [4 + 1] Cycloaddition of Biphenylene with Alkenes.

ABSTRACT: Recently, we reported an Ir-catalyzed formal [4 + 1] cycloaddition of biphenylenes with alkenes, which gave 9,9-disubstituted fluorenes in moderate to excellent yields. We proposed a reaction mechanism that involved the intermolecular insertion of alkenes, ?-elimination, and intramolecular insertion based on the results of experimental mechanistic studies. Herein, we further support the proposed mechanism by density functional theory calculations and explain why [4 + 1] cycloaddition proceeds rather than conventional [4 + 2] cycloaddition.

SUBMITTER: Takano H

PROVIDER: S-EPMC6641719 | biostudies-literature | 2017 Aug

REPOSITORIES: biostudies-literature

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DFT Studies on the Mechanism of the Iridium-Catalyzed Formal [4 + 1] Cycloaddition of Biphenylene with Alkenes.

Takano Hideaki H Sugimura Natsuhiko N Kanyiva Kyalo Stephen KS Shibata Takanori T

ACS omega 20170830 8

Recently, we reported an Ir-catalyzed formal [4 + 1] cycloaddition of biphenylenes with alkenes, which gave 9,9-disubstituted fluorenes in moderate to excellent yields. We proposed a reaction mechanism that involved the intermolecular insertion of alkenes, β-elimination, and intramolecular insertion based on the results of experimental mechanistic studies. Herein, we further support the proposed mechanism by density functional theory calculations and explain why [4 + 1] cycloaddition proceeds ra ...[more]

PMID: 31457794

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