Recent Advances in Palladium-Catalyzed Functionalization of Carbohydrate Frameworks

Carbohydrates are essential biomolecules that play critical roles in biological processes such as energy storage, cellular communication, and immune response regulation. Their structural complexity arises primarily due to the presence of various hydroxyl groups and stereocenters, which presents significant challenges for structural modification and functionalization. Traditional carbohydrate functionalization strategies often necessitate multiple protecting groups and harsh reaction conditions. This in turn limits their efficiency and synthetic flexibility. In recent years, transition metal catalysis, particularly palladium-mediated protocols, has emerged as a powerful tool for selective and efficient carbohydrate functionalization under mild conditions. Palladium catalysis has enabled diverse transformations, including glycosylation, C─C and C─X (X = O, N, S) bond formation, and regioselective derivatization, significantly expanding the chemical space of carbohydrates and glycoconjugates. This review provides a comprehensive analysis of recent advancements in palladium-catalyzed carbohydrate functionalization over the past 8 years, with a focus on synthetic strategies, mechanistic insights, and practical applications. By highlighting the latest developments and future directions, this review aims to serve as a valuable resource for the researchers working at the interface of carbohydrate chemistry, catalysis, and biomedical sciences.