Synthesis of Benzopyran Atropisomers via Electrophilic Halogenation
We report a halogenation‐based strategy for the synthesis of axially chiral benzopyrans, a rare and underexplored class of nonbiaryl atropisomers. The reaction exhibits broad substrate scope, tolerating both electron‐donating and electron‐withdrawing substituents, and accommodates the incorporation of bromine, chlorine, and iodine. A sequential double bromination enables the construction of bisbenzopyrans bearing two stereogenic axes. Preliminary enantioselective brominations catalyzed by chiral phosphoric acids delivered enantiomeric excesses of up to 56%. The method was successfully scaled to gram level and further elaborated through Suzuki coupling, highlighting its synthetic versatility. This work provides a new platform for the atroposelective synthesis of benzopyran‐based architectures.
Authors
- Expédite Yen‐Pon (ORCID: https://orcid.org/0000-0002-4283-9272)
- Damien Bonne (ORCID: https://orcid.org/0000-0003-4479-4626)
- Alix Bourhis
- Jean Rodriguez (ORCID: https://orcid.org/0000-0002-0094-3709)
Institutions
- Centre National de la Recherche Scientifique (FR)
- Centrale Méditerranée (FR)
Publication Details
- Journal
- European Journal of Organic Chemistry
- Published
- 2026-06-09
- DOI
- https://doi.org/10.1002/ejoc.70603
- Primary Topic
- Axial and Atropisomeric Chirality Synthesis
- Type
- article
- Field-Weighted Citation Impact
- 0.00