Catalytic conversion of carbohydrates into 5-hydroxymethylfurfural by Hafnium(IV) chloride in ionic liquids

Conversion of carbohydrates into HMF in ionic liquids (ILs) catalyzed by HfCl4 has been investigated in search of an efficient and environment-friendly process. The structure of ILs, catalyst loading, and reaction temperature had remarkable effects on this new catalytic system. Under optimal conditions, HMF yield up to 77.5% was obtained from fructose in 30?min at 100 degrees C. Moderate yields of HMF were also obtained from aldohexose such as glucose, cellobiose, even cellulose. Furthermore, a possible mechanism for carbohydrates conversion into HMF catalyzed by HfCl4 was proposed according to the configuration of valence shell of Hf. This work provides a meaningful method for the conversion of carbohydrates into fine chemicals.