Catalytic In Situ Acetalization Strategy for High-Yield Synthesis of C ₄ - and C ₂ -Carbohydrate Derivatives from Glucose

The development of heterogeneous catalytic upgrading processes for glucose, the most abundant carbohydrate in plant biomass, is crucial for advancing the production of renewable chemicals. Among the promising strategies, retro-aldolization enables direct and selective cleavage of C–C bonds, offering a route to valuable C4 and C2 carbohydrates: erythrose (ERT) and glycolaldehyde (GA). These compounds serve as key precursors to a range of high-value chemicals. However, their susceptibility to degradation by humin formation hinders practical implementation. Here, we present a catalytic strategy involving Nb2O5 and H-MOR zeolite for converting glucose in ethanol to ERT and GA through selective retro-aldolization (Nb2O5), followed by in situ acetalization to form the corresponding stable acetals of ERT and GA (H-MOR). Lewis acidic Nb5+ in NbO4 tetrahedra in the Nb2O5 surface catalyzes retro-aldolization of glucose, while Bro̷nsted acid sites in the H-MOR pores provide a shape-selective reaction environment for the acetalization of ERT and GA with ethanol. The exclusion of glucose from the one-dimensional micropores of H-MOR is critical to the high efficiency achieved. This method for glucose conversion in heterogeneous catalysis, based on protection principles common in synthetic organic chemistry, can impact the use of glucose as a feedstock for making renewable C4 and C2 chemicals.