No-carrier-added [18F]fluoroarenes from the radiofluorination of diaryl sulfoxides

Abstract

No-carrier-added [18F]fluoroarenes were synthesized through the radiofluorination of diaryl sulfoxides with [18F]fluoride ion. Diaryl sulfoxides bearing a para electron-withdrawing substituent readily gave the corresponding 4-[18F]fluoroarenes in high RCYs. This process broadens the scope for preparing novel 18F-labeling synthons and PET radiotracers.

Synthesis of [18F]Fluoroarenes by Nucleophilic Radiofluorination of N‐Arylsydnones

“…[4] Trimethylanilinium triflates, triarylsulfonium salts, [8] diarylsulfoxides, [9] and diarylselenones [10] are typical precursors used in S N Ar reactions (Scheme 1). Diaryliodonium salts [11] are also viable precursors which give moderate to good selectivity that can be significantly improved with a copper catalyst.…”

Spirocyclic hypervalent iodine(III)-mediated radiofluorination of non-activated and hindered aromatics

“…Other efforts to achieve this goal include applications of triarylsulphonium salts 9 , diarylsulphoxides 10 or the post-S N Ar conversion of activating, electron-withdrawing groups into electron-donating groups, for example, through Baeyer-Villiger oxidation 11 , all of which are based on reactions towards electron-deficient arenes and have limited substrate scope. Alternatively, transition-metal-mediated fluorination reactions (Fig.…”

Chemistry for Positron Emission Tomography: Recent Advances in 11C‐, 18F‐, 13N‐, and 15O‐Labeling Reactions

“…Representative PET tracers are shown in Scheme 18 B. Alternatively,m olecules with nonactivating substituents can also be synthesized through S N Ar conversion of arenes with electron-withdrawing groups, followed by post-S N Ar functional-group manipulations. [115] Ah igher reaction temperature (150-200 8 8C) was required, probably because of the low reactivity of diaryl sulfoxides.E lectron-deficient diaryl sulfoxides offered products with high RCCs,s uch as 1-[ 18 F]fluoro-4-nitrobenzene (78 %), whereas the labeling of electron-rich diaryl sulfoxides remained achallenge. [113] The 18 F-fluorination occurred preferentially at the relatively electron-deficient aryl group and the remaining diarylsulfonium group served as the leaving group.I n2 015, rstad and co-workers extended the substrate scope to electron-rich arenes by using diarylsulfonium compounds bearing para-methoxyphenyl groups as the leaving group (Scheme 19 A2).…”