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Updated: Nov 27, 2025

Application of Elemental Lanthanides in the Selective C-F Activation of Trifluoromethylated Benzofulvenes Providing Access to Various Difluoroalkenes
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Multifunctional Crown-5-calix[4]arene-based Phase-Transfer Catalysts for Aromatic 18F-Fluorination

Won Chang Lee1,2, Seok Min Kang3, Byung Chul Lee1,4

  • 1Department of Nuclear Medicine, Seoul National University Hospital, Seongnam 13620, Republic of Korea.

Organic Letters
|December 3, 2020
PubMed
Summary

Methylated bis-triethylene glycolic crown-5-calix[4]arene (M-BTC5A) excels as a phase-transfer catalyst for nucleophilic aromatic fluorination. It efficiently produces radiolabeled compounds like [18F]Flumazenil with high yields.

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