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.

Automated summary

Catalytic conversion of cellulose into 2,5-hexanedione (HXD) is an efficient method for high-value utilization of biomass resources. This study developed a one-pot conversion of cellulose into HXD with high yield using Al2(SO4)3 and Pd/C as catalysts. Al2(SO4)3 catalyzed the conversion of cellulose into intermediate HMF, while Pd/C and Al2(SO4)3 catalyzed the hydrogenolysis of HMF into furanic intermediates, which were further transformed into HXD by Al2(SO4)3. The catalytic system also showed excellent performance in converting glucose and sucrose into HXD.