Fluoride relay: a new concept for the rapid preparation of anhydrous nucleophilic fluoride salts from KF

Abstract

Fluoride relay is used to generate exceptionally nucleophilic fluoride reagents from KF on a time scale commensurate with radiotracer synthesis.

Competitive demethylation and substitution in N,N,N-trimethylanilinium fluorides

“…We are aided in these efforts by our recent synthesis of anhydrous tetrabutylammonium fluoride (TBAF*) [40], a convenient source of highly nucleophilic fluoride ion [41] that may be used for radiotracer synthesis [42].…”

Metal-catalysed halogen exchange reactions of aryl halides

“…Substitution via an S N Ar mechanism is possible on electron deficient compounds, and this is an 45 important method for the preparation of aryl fluorides [4][5][6][7] (Scheme 2, 13). However, a general transformation has yet to be developed for aromatic halogen exchange.…”

Microwave Accelerated Synthesis of PET Image Contrast Agents for AD Research

“…The combination of a polar aprotic solvent with activated nucleophile (F-) is particularly well suited to designing very rapid thermal reactions under microwave control, and thus they have become of importance in PET ligand design, as the following transformations will demonstrate. Using nitroaryl substrates and anhydrous TBAF, fluorodenitrations can routinely be achieved in <10 min (Scheme 1, 3) [3,14]. We and others have applied this technology to preparation of a large number of aryl and heteroaryl substrates, both monocyclic and bicyclic, to great effect [3].…”