One-Pot Conversion of Cellulose into 2,5-Hexanedione in H2O-Tetrahydrofuran Co-Solvents

Catalytic conversion of cellulose into the novel platform molecule 2,5-hexanedione (HXD) is regarded as one feasible approach for high-value utilization of biomass resources. Here, we reported one efficient way of one-pot conversion of cellulose into HXD with high yield of 80.3% in H2O and tetrahydrofuran (THF) mixture within Al2(SO4)3 combined with Pd/C as a catalyst. In the catalytic reaction system, Al2(SO4)3 could catalyze the conversion of cellulose into 5-hydroxymethylfurfural (HMF), and Pd/C combined with Al2(SO4)3 could catalyze the hydrogenolysis of HMF into furanic intermediates such as 5-methylfurfuryl alcohol and 2,5-dimethylfuran (DMF) without causing over-hydrogenation of these furanic intermediates. These furanic intermediates were finally transformed into HXD catalyzed by Al2(SO4)3. Besides, the H2O/THF ratio could significantly influence the reactivity of the hydrolytic furanic ring-opening of the furanic intermediates. The catalytic system also showed excellent performance on the conversion of other carbohydrates (glucose and sucrose) into HXD.