Synthesis of N tau-arylhistidine derivatives via direct N-arylation.

N(tau)-Aryl-histidine derivatives were synthesized using a modified one-step Cu-catalyzed coupling of aryl halides and N-acetylhistidine methyl ester. The latter is much less reactive than imidazole toward aryl halides. p-Chloroiodobenzene coupled with iodine displacement only, whereas m- and p-bromoiodobenzene both gave mixtures of bromo- and iodophenyl products.