Isomerization of glucose to fructose catalyzed by MgCl2 in water

Saccharide is the main product of biomass hydrolysis, which can be converted into high-value-added chemicals and fuels, and the isomerization of glucose to fructose is a decisive step in biomass conversion technology. In this research, the isomerization reaction of glucose catalyzed by MgCl 2 -700 in water has been studied, and the fructose yield and selectivity reached 36.4 % and 79.3 %, respectively in an aqueous system at 120 °C for 60 min. The results of electrospray ionization tandem mass spectrometry (ESI-MS) and density functional theory (DFT) show that [MgCl(aq)] + formed in an aqueous system coordinated with glucose for isomerization reaction, and the binding of C1/C2 sites of the β-glucopyranose and [MgCl(aq)] + promoted the 1,2-intramolecular hydride shift of glucose, thus rapidly converting glucose into fructose.