Catalytic coupling boosting efficient production of 5‐hydroxymethylfurfural from glucose

As a novel green chemical building block, it is of significance to increase the productivity of 5‐hydroxymethylfurfural (HMF) derived from hexoses. In our work, a catalytic system efficiently converting glucose to HMF was designed, which is guided by catalytic coupling at multiple length scales. A catalyst from the sulfonated and carbonized glucose with aluminum loading containing Lewis and Brønsted acidic sites, along with tetrahydrofuran/H 2 O‐NaCl featuring low boiling point and biphasic solvent, was introduced to the catalytic conversion of glucose. Not only the HMF yield of 75% from glucose was achieved at 140°C for 8 h but also the purity of HMF went up to 93% by facile separation and evaporation. In the reuse of the catalysts, the selectivity of HMF was basically maintained at 81% with the conversion of glucose decreasing by ca. 20% after five runs.