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Updated: Jun 7, 2025
![Radiosynthesis of 1-2-[18F]Fluoroethyl-L-Tryptophan using a One-pot, Two-step Protocol](/_next/image?url=https%3A%2F%2Fcloudfront.jove.com%2FCDNSource%2Fteasers%2F63025.jpg&w=3840&q=50)
Radiosynthesis of 1-2-[18F]Fluoroethyl-L-Tryptophan using a One-pot, Two-step Protocol
Published on: September 21, 2021
Triflyl [18F]Fluoride as a Solution for Base-Sensitive Late-Stage Nucleophilic Aromatic 18F-Fluorination Reactions
Lizeth Y F Haveman1, Anna M T de Kruijff1, Sjoerd P P van Eeden1
1Deparment of Radiology & Nuclear Medicine, Amsterdam UMC, location Vrije Universiteit Amsterdam, De Boelelaan 1117, 1081 HV, Amsterdam, The Netherlands.
Abstract:
Fluorine-18 is the predominant radionuclide used to label Positron Emission Tomography (PET) tracers. One outstanding challenge in nucleophilic aromatic radiofluorination reactions is the sensitivity of precursors and catalysts for basic reaction conditions, which are necessary for the work-up of [18F]fluoride, resulting in limited reproducibility. Triflyl [18F]fluoride is a new [18F]fluoride source that allows freedom in choice of type and amounts of base and cryptand. The aim of the current work is to explore the scope and limitations of triflyl [18F]fluoride in the late-stage nucleophilic aromatic 18F-fluorination of various functionalized precursors, exploring reduced amounts of base and cryptand. The assessment allowed for the application of this new nucleophilic [18F]fluoride reagent to the successful radiosynthesis of boron, stannane, hypervalent iodonium ylide and phenol substrates bearing electron-deficient, -neutral and -rich functional groups as well as the clinically relevant PET tracers [18F]FPEB, [18F]mFBG and [18F]SynVesT-1.
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