2D MOF with Compact Catalytic Sites for the One-pot Synthesis of 2,5-Dimethylfuran from Saccharides via Tandem Catalysis.

One pot synthesis of 2,5-dimethylfuran (2,5-DMF) from saccharides under mild conditions is of importance for the production of biofuel and fine chemicals. However, the synthesis requires a multitude of active sites and suffers from slow kinetics due to poor diffusion in most composite catalysts. Herein, a metal-acid functionalized 2D metal-organic framework (MOF; Pd/NUS-SO3 H), as an ultrathin nanosheet of 3-4 nm with Lewis acid, Brønsted acid, and metal active sites, was prepared based on the diazo method for acid modification and subsequent metal loading. This new composite catalyst gives substantially higher yields of DMF than all reported catalysts for different saccharides (fructose, glucose, cellobiose, sucrose, and inulins). Characterization suggests that a cascade of reactions including polysaccharide hydrolysis, isomerization, dehydration, and hydrodeoxygenation takes place with rapid molecular interactions.