Chlorinated Paracyclophanes: Composition Analysis and Direct Metal‐Free Alkylation with <i>n</i> ‐BuLi
A transition‐metal‐free alkylation of the dichloro[2.2]paracyclophane scaffold is reported, representing a significant advancement in the reactivity of this unique class of compounds. The pseudo‐ para isomer of dichloro[2.2]paracyclophane was isolated from a commercial mixture via crystallization, and its structure was assessed by detailed 1D and 2D NMR spectroscopy. The reaction of the purified isomer with butyllithium was investigated, and a systematic optimization revealed that reaction rate and selectivity were significantly improved by using a chelating agent and conducting the reaction in refluxing heptane. This refined protocol yielded the desired dialkylated product, establishing a new and more efficient synthetic pathway that opens the door to further exploration of this unprecedented reactivity.
Authors
- Fabrizio Menchini Fabris (ORCID: https://orcid.org/0000-0001-9209-1680)
- Davide Frigatti (ORCID: https://orcid.org/0000-0003-3772-3539)
- Alessandro Scarso (ORCID: https://orcid.org/0000-0001-6114-9181)
- Stefan Bräse (ORCID: https://orcid.org/0000-0003-4845-3191)
Institutions
- Karlsruhe Institute of Technology (DE)
- Ca' Foscari University of Venice (IT)
- Kerntechnische Entsorgung Karlsruhe (Germany) (DE)
Publication Details
- Journal
- European Journal of Organic Chemistry
- Published
- 2026-02-25
- DOI
- https://doi.org/10.1002/ejoc.202501150
- Primary Topic
- Coordination Chemistry and Organometallics
- Type
- article
- Field-Weighted Citation Impact
- 0.00