A core-shell type of polymer-supported N-heterocyclic carbene (NHC) palladium catalyst was applied to Sonogashira cross-coupling reactions without copper cocatalyst under ambient atmosphere. This supported NHC–palladium complex efficiently catalyzed the copper-free Sonogashira reaction of various aryl iodides and bromides with terminal alkynes; the reaction exhibited high dependency on the temperature and the amount of ...
