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Cu-Mediated C-H 18F-Fluorination of Electron-Rich (Hetero)arenes.

ABSTRACT: This communication describes a method for the nucleophilic radiofluorination of electron-rich arenes. The reaction involves the initial C(sp2)-H functionalization of an electron-rich arene with MesI(OH)OTs to form a (mesityl)(aryl)iodonium salt. This salt is then used in situ in a Cu-mediated radiofluorination with [18F]KF. This approach leverages the stability and availability of electron-rich arene starting materials to enable mild late-stage radiofluorination of toluene, anisole, aniline, pyrrole, and thiophene derivatives. The radiofluorination has been automated to access a 41 mCi dose of an 18F-labeled nimesulide derivative in high (2800 ± 700 Ci/mmol) specific activity.

SUBMITTER: McCammant MS

PROVIDER: S-EPMC5525103 | biostudies-literature | 2017 Jul

REPOSITORIES: biostudies-literature

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Cu-Mediated C-H 18F-Fluorination of Electron-Rich (Hetero)arenes.

McCammant Matthew S MS Thompson Stephen S Brooks Allen F AF Krska Shane W SW Scott Peter J H PJH Sanford Melanie S MS

Organic letters 20170630 14

This communication describes a method for the nucleophilic radiofluorination of electron-rich arenes. The reaction involves the initial C(sp2)-H functionalization of an electron-rich arene with MesI(OH)OTs to form a (mesityl)(aryl)iodonium salt. This salt is then used in situ in a Cu-mediated radiofluorination with [18F]KF. This approach leverages the stability and availability of electron-rich arene starting materials to enable mild late-stage radiofluorination of toluene, ...[more]

PMID: 28665619

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