Fructose hydrogenation products from

Normally, however, the reaction involving the formation of hydroxy-methylfurfural proceeds less readily than does the hydrogenation of glucose and fructose to mannitol and sorbitol, but its occurrence is detected by the fact that tetrahydrofuran derivatives have been isolated from the hydrogenation products. Thus, we have isolated tetrahydrofuran 2,5-dicarbinol (identified as its ditosyl derivative), 5-methyltetra-hydrofurfuryl alcohol and 2,5-dimethyltetrahydrofuran (VII) together with hydrogenolysis products of these compounds. 

Reaction of D-fructose with potassium thiocyanate in the presence of hydrogen chloride affords a thiooxazoline derivative of unknown structure. From indirect evidence, formula (59) was suggested, as all attempts to isolate the amino sugar expected from structure (58) have been fruitless. In contrast, the D-glucosylamine and even the di-n-glucosylamine compound were found, by chromatography, as products from the corresponding... 

Complete reduction of HMF to 2,5-dimethyltetrahydrofuran (DMTHF) 15 was studied in detail by Sen and co-workers, where not only HMF but also fructose could be cOTiverted to DMTHF by hydrogenation in the presence of HI and a ruthenium catalyst [97, 98]. Despite the high energy content of DMTHF and its potential as a fuel, comparatively few studies have been devoted to its selective production from HMF or biomass in general. 

The Amadori rearrangement also occurs for the glycosylamine derivatives of some secondary alkylamines and of primary and secondary aralkyl-amines it occurs in alcoholic solution in the presence of compounds such as ethyl malonate and acetylacetone which contain active hydrogen atoms 66), The direct reaction product from D-glucose and dibenzylamine was actually 1-dibenzylamino-l-deoxy-D-fructose (XI) 66) and not VjV-di-benzyl-D-glucosylamine (XII) as indicated earlier by Kuhn and Birkofer 76), This rearrangement was effected without benefit of acid catalysis 70) or by the use of ethyl malonate 66), The true V,i T-dibenzylglu-cosylamine (XII) could not be isolated. 

Harrison, Tarr and Hibbert96 investigated the production of levan from sucrose by the action of Bacillus subtilis Cohn and B. mesentericus Trevisan. Nutrient solutions containing 10% carbohydrate, 0.1% peptone, 0.2% disodium hydrogen phosphate and 0.5% potassium chloride were incubated at 37° for six days. Levan formation occurred only with sucrose and raffinose, and not with melezitose, lactose, maltose, D-xylose, D-glucose or D-fructose. It was therefore suggested that only those carbohydrates with a terminal D-fructofuranose residue were satisfactory substrates for levan formation. 

Sorbitol is produced by high-pressure catalytic hydrogenation of glucose derived from cornstarch. It can also be produced as a co-product with mannitol if invert sugar (50% glucose, 50% fructose) is used as raw material. 

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