A Critical Review of Catalytic Glucose‐to‐Fructose Isomerization

ABSTRACT In the context of renewable chemical production, the isomerization of glucose‐to‐fructose represents a key transformation underpinning the synthesis of platform chemicals and biofuels from biomass. This review summarizes the recent progress in nonenzymatic glucose isomerization, with emphasis on three mechanistic paradigms: base‐catalyzed enediol rearrangement, Lewis acid–mediated 1,2‐hydride shift, and acid/base coordination pathways. We provide a comparative evaluation of alkaline (sodium‐based, magnesium‐based, calcium‐based, lithium‐based, organic base, and composite), Lewis acid (tin‐based, aluminum‐based, metal oxide, chloride‐based, metal–organic framework, and titanates), and bifunctional (layered double hydroxides, mixed metal oxides, organic–inorganic hybrid, and amphoteric and redox‐assisted oxides) catalysts in terms of activity, selectivity, recyclability, and scalability. Particular attention is given to trade‐offs between catalytic efficiency and leaching or deactivation, which limit industrial feasibility. Emerging innovations—such as continuous‐flow systems and catalyst design with machine learning—are also discussed. Finally, we identify future opportunities for integrating mechanistic insights with catalyst design principles to advance green, cost‐effective glucose isomerization pathways.