title: One-pot conversions of raffinose into furfural derivatives and sugar alcohols by using heterogeneous catalysts.
abstract: Inedible and/or waste biomass reserves are being strongly focused upon as a suitable new energy and chemical source. Raffinose, which is an indigestible trisaccharide composed of glucose, galactose, and fructose, is found abundantly in beet molasses, sugar cane, and seeds of many leguminous plants. Herein, we demonstrate the one-pot synthesis of furan derivatives and sugar alcohols from raffinose by using heterogeneous acid, base, and/or metal-supported catalysts. The combination of Amberlyst-15 and hydrotalcite (HT) showed a high activity (37% yield) for 5-hydroxymethyl-2-furaldehyde (HMF) through continuous hydrolysis, isomerization, and dehydration reactions. In addition, the use of a hydrotalcite-supported ruthenium catalyst (Ru/HT) successfully afforded 2,5-diformylfuran (DFF, 27% yield) from HMF produced by raffinose, directly. Moreover, the hydrogenation of hexoses obtained by raffinose hydrolysis into sugar alcohols (galactitol, mannitol, sorbitol) was also achieved in a high yield (91%) with Amberlyst-15 and Ru/HT catalysts. Thus, we suggest that raffinose has great potential for the synthesis of important industrial intermediates under mild reaction conditions.
authors.affiliation: School of Materials Science, Japan Advanced Institute of Science and Technology (JAIST), 1-1 Asahidai, Nomi, 923-1292 (Japan), Fax: (+81) 761-51-1149; M. Tech, C.S.P.T, Department of Chemistry, Faculty of Science, University of Delhi (DU), University Road, Delhi, 110007 (India).
authors.forename: Saumya
authors.initials: S
authors.lastname: Dabral
authors.forename: Shun
authors.initials: S
authors.lastname: Nishimura
authors.forename: Kohki
authors.initials: K
authors.lastname: Ebitani
mesh_terms: D000536:Aluminum Hydroxide / Q000737:chemistry; D002384:Catalysis; D005662:Furaldehyde / Q000031:analogs & derivatives* / Q000737:chemistry; D005663:Furans / Q000737:chemistry*; D008276:Magnesium Hydroxide / Q000737:chemistry; D011887:Raffinose / Q000737:chemistry*; D012428:Ruthenium / Q000737:chemistry; D013343:Styrenes / Q000737:chemistry; D013402:Sugar Alcohols / Q000737:chemistry*
chemical_list: D005663:Furans; D013343:Styrenes; D013402:Sugar Alcohols; C528218:amberlyst-15; C010467:hydrotalcite; D000536:Aluminum Hydroxide; C008046:5-hydroxymethylfurfural; D012428:Ruthenium; D005662:Furaldehyde; C476922:2,5-diformylfuran; D011887:Raffinose; D008276:Magnesium Hydroxide
keywords: carbohydrates; furans; heterogeneous catalysis; one-pot reactions; renewable resources