Selected Transition Metals for Efficient Triazole Synthesis in Click Chemistry: Beyond Copper Catalysis

ABSTRACT Click chemistry has emerged as an effective method for synthesizing triazoles via copper(I)‐catalyzed azide–alkyne cycloaddition. The high efficiency and regioselectivity of copper catalysis have established it as a standard method for triazole synthesis; however, its application is associated with notable limitations, particularly cytotoxicity, challenges in controlling oxidation state, and undesirable effects in biological environments. This review examines the role of selected transition metals, including scandium, rhodium, zinc, iridium, silver, nickel, palladium, and iron, as viable alternatives to copper in click chemistry, specifically metal‐catalyzed azide‐alkyne cycloaddition. These catalytic systems are discussed in terms of their ability to overcome copper‐related drawbacks while maintaining high yields and functional group tolerance. Applications of transition metal‐catalyzed triazole synthesis in materials science, bioconjugation, biological applications, and drug development are reviewed.