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Programmed Polyene Cyclization Enabled by Chromophore Disruption.

ABSTRACT: A new polyene cyclization strategy exploiting β-ionyl derivatives was developed. Photoinduced deconjugation of the extended π-system within these chromophores unveils a contrathermodynamic polyene that engages in a Heck bicyclization to afford [4.4.1]-propellanes. This cascade improves upon the limited regioselectivity achieved using existing biomimetic tactics and tolerates both electron-rich and electron-deficient (hetero)aryl groups. The utility of this approach was demonstrated with the diverted total synthesis of taxodione and salviasperanol, two isomeric abietane diterpenes that were previously inaccessible along the same synthetic pathway.

SUBMITTER: Solans MM

PROVIDER: S-EPMC10559755 | biostudies-literature | 2022 Apr

REPOSITORIES: biostudies-literature

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Programmed Polyene Cyclization Enabled by Chromophore Disruption.

Solans Megan M MM Basistyi Vitalii S VS Law James A JA Bartfield Noah M NM Frederich James H JH

Journal of the American Chemical Society 20220404 14

A new polyene cyclization strategy exploiting β-ionyl derivatives was developed. Photoinduced deconjugation of the extended π-system within these chromophores unveils a contrathermodynamic polyene that engages in a Heck bicyclization to afford [4.4.1]-propellanes. This cascade improves upon the limited regioselectivity achieved using existing biomimetic tactics and tolerates both electron-rich and electron-deficient (hetero)aryl groups. The utility of this approach was demonstrated with the dive ...[more]

PMID: 35377634

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