title: Catalytic conversion of carbohydrates into 5-hydroxymethylfurfural by germanium(IV) chloride in ionic liquids.
abstract: Direct conversion of carbohydrates into 5-hydroxymethylfurfural (HMF) catalyzed by germanium(IV) chloride in ionic liquids has been investigated in search of an efficient and environmentally friendly process. Monosaccharides D-fructose and D-glucose, disaccharides sucrose and maltose, and even the polysaccharide cellulose were successfully converted into HMF with good yields under mild conditions (yield up to 92 % in 5 min in the case of fructose). The structure of ionic liquids, catalyst loading, reaction temperature and water content had noticeable effects on this catalytic system. Addition of 5 Å molecular sieves during the dehydration of glucose resulted in an increase in HMF yield from 38.4 % to 48.4 %. A mechanism for glucose conversion to HMF catalyzed by germanium(IV) chloride was proposed according to ¹³C NMR spectra obtained in situ under different conditions using D-glucose-2-¹³C as the substrate.
authors.affiliation: Dalian Institute of Chemical Physics, CAS, China.
authors.forename: Zehui
authors.initials: Z
authors.lastname: Zhang
authors.forename: Qian
authors.initials: Q
authors.lastname: Wang
authors.forename: Haibo
authors.initials: H
authors.lastname: Xie
authors.forename: Wujun
authors.initials: W
authors.lastname: Liu
authors.forename: Zongbao Kent
authors.initials: ZK
authors.lastname: Zhao
mesh_terms: D002241:Carbohydrates / Q000737:chemistry*; D002384:Catalysis; D005662:Furaldehyde / Q000031:analogs & derivatives* / Q000737:chemistry; D005947:Glucose / Q000737:chemistry; D007093:Imidazoles / Q000737:chemistry; D052578:Ionic Liquids / Q000737:chemistry*; D009942:Organometallic Compounds / Q000737:chemistry*; D012492:Salts / Q000737:chemistry; D013696:Temperature; D014867:Water / Q000737:chemistry
chemical_list: C525963:1-butyl-3-methylimidazolium; D002241:Carbohydrates; D007093:Imidazoles; D052578:Ionic Liquids; D009942:Organometallic Compounds; D012492:Salts; D014867:Water; C557680:germanium chloride; C008046:5-hydroxymethylfurfural; D005662:Furaldehyde; D005947:Glucose