Abstract: 5-Iodouracil derivatives have interesting biological activities and can serve as important substrates for the metal-catalyzed cross-coupling reactions to introduce alkyl, alkenyl, and alkynyl groups to the C-5 position of uracil derivatives. In order to find a good method to iodinate directly the C-5 of uracil derivatives, we investigated three methods, which included iodine/lead (IV) dioxide, iodine/ammonium hexanitratocerate (CAN) and iodine chloride, and examined their reactivity to different types of uracil and thiouracil derivatives.

Key words: Iodination, Lead (IV) dioxide, Ammonium hexanitratocerate, Iodine chloride, Uracil, 2-Thiouracil