Work

Chlorinated Paracyclophanes: Composition Analysis and Direct Metal‐Free Alkylation with n ‐BuLi

Year: 2026

Type: article

Abstract: 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.

Source: European Journal of Organic Chemistry

DOI: 10.1002/ejoc.202501150

Authors: Davide Frigatti, Alessandro Scarso, Stefan Bräse, Fabrizio Fabris

Institutions: Ca' Foscari University of Venice, Karlsruhe Institute of Technology

Language: English

Topic: Synthesis and Properties of Aromatic Compounds

Subfield: Organic Chemistry

Field: Chemistry

Domain: Physical Sciences

Open Access status: hybrid

Estimated APC paid: $4,330

Funder: Università Ca' Foscari Venezia