Reductive amination of [18F]fluorobenzaldehydes: Radiosyntheses of [2‐18F]‐ and [4‐18F]fluorodexetimides

Abstract

AbstractTwo [18F]‐labelled analogues of dexetimide, a potent muscarinic cholinergic receptor ligand, have been synthesised in good yields and at high specific activities. Reductive amination of [2‐18F]‐ and [4‐18F]fluorobenzaldehyde with norbenzyldexetimide and sodium cyanoborohydride gave, in a one‐pot reaction, good (≈︁20%) yields of high specific activity [2‐18F]‐ and [4‐18F]fluorodexetimide respectively. The labelled benzaldehydes may be useful synthetic precursors for the radiosyntheses of other complex radiotracers for use with positron emission tomography.