A novel iodine-promoted tandem cyclization: An efficient synthesis of substituted 3,4-diiodoheterocyclic compounds

摘要

(Figure Presented) Iodine sets allenes ringing: A novel iodine-promoted tandem cyclization reaction of but-2-yne-1,4-diol and 4aminobut-2-yn-l-ol derivatives leading to substituted 3, 4-diiodoheterocyclic compounds has been developed (see scheme). In this reaction, a trace amount of water is needed. Both the iodine anion and cation generated from I_2 are used in the reaction. The resulting iodides can then be used in palladium-catalyzed coupling reactions. The reaction conditions are metal-free, mild, and environmentally friendly.