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Titania-catalyzed radiofluorination of tosylated precursors in highly aqueous medium.

ABSTRACT: Nucleophilic radiofluorination is an efficient synthetic route to many positron-emission tomography (PET) probes, but removal of water to activate the cyclotron-produced [(18)F]fluoride has to be performed prior to reaction, which significantly increases overall radiolabeling time and causes radioactivity loss. In this report, we demonstrate the possibility of (18)F-radiofluorination in highly aqueous medium. The method utilizes titania nanoparticles, 1:1 (v/v) acetonitrile-thexyl alcohol solvent mixture, and tetra-n-butylammonium bicarbonate as a phase-transfer agent. Efficient radiolabeling is directly performed with aqueous [(18)F]fluoride without the need for a drying/azeotroping step to significantly reduce radiosynthesis time. High radiochemical purity of the target compound is also achieved. The substrate scope of the synthetic strategy is demonstrated with a range of aromatic, aliphatic, and cycloaliphatic tosylated precursors.

SUBMITTER: Sergeev ME

PROVIDER: S-EPMC4485375 | biostudies-literature | 2015 May

REPOSITORIES: biostudies-literature

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Titania-catalyzed radiofluorination of tosylated precursors in highly aqueous medium.

Sergeev Maxim E ME Morgia Federica F Lazari Mark M Wang Christopher C van Dam R Michael RM

Journal of the American Chemical Society 20150422 17

Nucleophilic radiofluorination is an efficient synthetic route to many positron-emission tomography (PET) probes, but removal of water to activate the cyclotron-produced [(18)F]fluoride has to be performed prior to reaction, which significantly increases overall radiolabeling time and causes radioactivity loss. In this report, we demonstrate the possibility of (18)F-radiofluorination in highly aqueous medium. The method utilizes titania nanoparticles, 1:1 (v/v) acetonitrile-thexyl alcohol solven ...[more]

PMID: 25860121

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