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A novel stereoselective [8+2] double cycloaddition route to hydronaphthalene ring systems.

ABSTRACT: Substituted hydronaphthalenes where each of the ten carbons of the two-ring system contains functionality were obtained through a tandem [8+2] cycloaddition and base-catalyzed rearrangement process using dienylfurans and electron-deficient alkynes. If the [8+2] process is conducted under solvent-free conditions the process could be conducted in a single reaction flask without isolation of the chromatographically sensitive [8+2] cycloadducts. A mechanism involving base catalysed alkene positional isomerization followed by disrotatory electrocyclic ring closure was proposed for the key reaction step that converts [8+2] cycloadducts to hydronaphthalenes. The products undergo selective ring opening-isomerization processes upon treatment with Lewis acids.

SUBMITTER: Ying W

PROVIDER: S-EPMC5082427 | biostudies-literature | 2016 Jul

REPOSITORIES: biostudies-literature

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A novel stereoselective [8+2] double cycloaddition route to hydronaphthalene ring systems.

Ying Weijiang W Zhang Lei L Wiget Paul A PA Herndon James W JW

Tetrahedron letters 20160517 27-28

Substituted hydronaphthalenes where each of the ten carbons of the two-ring system contains functionality were obtained through a tandem [8+2] cycloaddition and base-catalyzed rearrangement process using dienylfurans and electron-deficient alkynes. If the [8+2] process is conducted under solvent-free conditions the process could be conducted in a single reaction flask without isolation of the chromatographically sensitive [8+2] cycloadducts. A mechanism involving base catalysed alkene positional ...[more]

PMID: 27795589

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