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Updated: Mar 7, 2026

Light Enhanced Hydrofluoric Acid Passivation: A Sensitive Technique for Detecting Bulk Silicon Defects
Published on: January 4, 2016
Crown Ether Nucleophilic Catalysts (CENCs): Agents for Enhanced Silicon Radiofluorination
Susovan Jana1, Mohammed H Al-Huniti1, Bo Yeun Yang2
1Department of Chemistry and Biochemistry, Florida Atlantic University , Boca Raton, Florida 33431-0991, United States.
Abstract:
New bifunctional phase transfer agents were synthesized and investigated for their abilities to promote rapid fluorination at silicon. These agents, dubbed crown ether nucleophilic catalysts (CENCs), are 18-crown-6 derivatives containing a side-arm and a potentially nucleophilic hydroxyl group. These CENCs proved efficacious in the fluorination of hindered silicon substrates, with fluorination yields dependent on the length of linker connecting the metal chelating unit to the hydroxyl group. The efficacy of these CENCs was also demonstrated for rapid radiofluorination under mild conditions for eventual application in molecular imaging with positron emission tomography (PET). The hydrolysis-resistant aryl silicon fragment is promising as a convenient synthon for labeling potential PET radiotracers.
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