Key Laboratory of Biofuels, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, 189 Songling Road, Qingdao 266101, People's Republic of China.
Carbohydr Res. 2011 May 15;346(7):956-9. doi: 10.1016/j.carres.2011.03.015. Epub 2011 Mar 12.
Conversion of fructose and glucose into 5-hydroxymethylfurfural (HMF) was investigated in various imidazolium ionic liquids, including 1-butyl-3-methylimidazolium chloride (BmimCl), 1-hexyl-3-methylimidazolium chloride (HmimCl), 1-octyl-3-methylimidazolium chloride (OmimCl), 1-benzyl-3-methylimidazolium chloride (BemimCl), 1-Butyl-2,3-dimethylimidazolium chloride (BdmimCl), and 1-butyl-3-methylimidazolium p-toluenesulfonate (BmimPS). The acidic C-2 hydrogen of imidazolium cations was shown to play a major role in the dehydration of fructose in the absence of a catalyst, such as sulfuric acid or CrCl(3). Both the alkyl groups of imidazolium cations and the type of anions affected the reactivity of the carbohydrates. Although, except BmimCl and BemimCl, other four ionic liquids could only achieve not more than 25% HMF yields without an additional catalyst, 60-80% HMF yields were achieved in HmimCl, BdmimCl, and BmimPS in the presence of sulfuric acid or CrCl(3) in sufficient quantities.
研究了果糖和葡萄糖在各种咪唑鎓离子液体中的转化为 5-羟甲基糠醛（HMF），包括 1-丁基-3-甲基咪唑氯（BmimCl）、1-己基-3-甲基咪唑氯（HmimCl）、1-辛基-3-甲基咪唑氯（OmimCl）、1-苄基-3-甲基咪唑氯（BemimCl）、1-丁基-2,3-二甲基咪唑氯（BdmimCl）和 1-丁基-3-甲基咪唑对甲苯磺酸盐（BmimPS）。在没有催化剂（如硫酸或 CrCl(3)）的情况下，咪唑鎓阳离子的酸性 C-2 氢被证明在果糖的脱水反应中起主要作用。咪唑鎓阳离子的烷基和阴离子的类型都影响碳水化合物的反应性。尽管除了 BmimCl 和 BemimCl 之外，其他四种离子液体在没有额外催化剂的情况下只能达到不超过 25%的 HMF 产率，但在硫酸或 CrCl(3)的存在下，HmimCl、BdmimCl 和 BmimPS 可以达到 60-80%的 HMF 产率。
