Main Group Metals in Redox Catalysis

Main group metal redox catalysis is no longer a curiosity; it is a credible challenger to transition metal chemistry. Heavy p ‐block elements, once dismissed as redox‐inert or limited to Lewis acid reactivity, now can execute the core elementary steps of catalysis, including coordination, oxidative addition, reductive elimination, transmetalation, and single‐electron transfer events. This review surveys recent advances across groups 13–15, focusing on aluminum, germanium, tin, antimony, and bismuth, the elements that have begun to deliver genuine metal‐centered redox catalytic performance. Reactivity is unlocked not by formal oxidation state alone, but by careful ligand design and through ambiphilicity, weak bonding, element–ligand cooperation, and access to open‐shell manifolds. The field is advancing fast, but unevenly. Group 13 is just getting started, whereas Ge, Sn, Sb, and especially Bi already operate across both two‐electron and radical regimes. Beyond summarizing progress, this review identifies emerging design principles, exposes mechanistic gaps, and highlights opportunities that are likely to decide what comes next. Heavy p ‐block elements are no longer just substitutes to transition metals. They are competitors, and increasingly, they are setting the terms for sustainable catalysis.