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Synlett
DOI: 10.1055/a-2772-4490
Letter
Published as part of the Special Topic Alkynes in Organic Synthesis

Photochemical Synthesis of 7,14-Dialkynyl-10,11-Dimethyl[5]Helicene via Flow Chemistry and Comparison with its Bromo Analog

Autor*innen

  • Anselm Uhlmann

    1   Institute of Organic Chemistry, Albert-Ludwigs-Universität Freiburg, Freiburg, Germany (Ringgold ID: RIN9174)

  • Jacques Guyon

    1   Institute of Organic Chemistry, Albert-Ludwigs-Universität Freiburg, Freiburg, Germany (Ringgold ID: RIN9174)

  • Daniel B. Werz

    1   Institute of Organic Chemistry, Albert-Ludwigs-Universität Freiburg, Freiburg, Germany (Ringgold ID: RIN9174)

Funding Information The authors are grateful to the Albert-Ludwigs-Universität Freiburg for funding.
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Graphical Abstract

Abstract

A flow photoreactor for the photochemical synthesis of substituted [5]helicenes from corresponding distilbenes is described. This method allows to circumvent scale limitations often associated with such reactions due to the high dilutions required. Additionally, reaction times can be significantly reduced by utilizing flow conditions. The syntheses of both, a known bromo-substituted helicene and a novel alkynyl-substituted helicene, are compared for both, batch and flow.

Keywords

Mallory reaction - Synthetic photochemistry - Flow chemistry - Helicenes - Alkynes

Supplementary Material



Publikationsverlauf

Eingereicht: 30. Oktober 2025

Angenommen nach Revision: 12. Dezember 2025

Accepted Manuscript online:
15. Dezember 2025

Artikel online veröffentlicht:
23. Januar 2026

© 2026. Thieme. All rights reserved.

Georg Thieme Verlag KG
Oswald-Hesse-Straße 50, 70469 Stuttgart, Germany

 

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