Synthesis of a chiral precursor for no-carrier-added (NCA) PET tracer 6- [18F]fluoro-L-dopa based on regio- and enantioselective alkylation of 2,4- bis(chloromethyl)-5-iodoanisole

Article abstract of DOI:10.1246/bcsj.73.417

(2S,5S)-5-(3-Formyl-6-iodo-4-methoxybenzyl)-1-t-butoxycarbonyl-2-t- butyl-3-methyl-4-imidazolidinone (11), a chiral intermediate towards NCA PET tracer 6-[₁₈F]fluoro-L-dopa (1), was synthesized from 3-iodoanisole in four steps. 3-Iodoanisole was first bischloromethylated to 2,4-bis(chloromethyl)- 5-iodoanisole (14). Regio- and enantio-selective alkylation of 14 with (S)-1- (t-butoxycarbonyl)-2-t-butyl-3-methyl-4-imidazolidinone (12) afforded 33, which was then hydrolyzed and oxidized to the desired intermediate 11.