Abstract: Transition-metal-catalyzed allylic substitution reactions are a fundamental topic in organometallic chemistry education. In addition to palladium, metals such as iridium, copper, cobalt, and nickel are also capable of catalyzing these reactions, each exhibiting distinct catalytic behaviors. However, traditional undergraduate courses often focus narrowly on palladium, failing to emphasize how the choice of transition metal critically directs reaction pathways and outcomes. To address this, we present a comparative study of Pd- and Ir-catalyzed allylic substitution as a pedagogical model. By systematically examining their mechanistic pathways along with regioselectivity profiles, we highlight how catalyst structure governs reactivity—a key conceptual thread in organometallic chemistry.

Key words: Organometallic chemistry, Palladium catalysis, Iridium catalysis, Allylic substitution, Comparative Pedagogy