Sucrose carbonate

A. Wernicke, S. Belniak, S. Thevenet, G. Descotes, A. Bouchu, and Y. Queneau, Synthesis of sucrose carbonates in aqueous medium, J. Chem. Soc., Perkin Trans., 1 (1998) 1179-1181. 

A recent potentiometric study supports the view of Siegfried and Howw-janz that, in solution at least, a complex calcium sucrose carbonate can exist. 

Mesoporous carbon was obtained by sucrose carbonization in the pores of MCM-4 silica spheres with subsequently dissolution of the silica. The carbon was impregnated with the ZSM-5 synthesis gel and the crystallization was carried out under hydrothermal conditions. After burning off the carbon, ZSM-5 with a bimodal mesopore system showing mean diameters around 2 and 30 nm was obtained. Nevertheless, the hexagonal pore array of the MCM-41 was not reproduced in the ZSM-5. 

Several monolithic enzyme biocatalysts were prepared and characterized with carbon coatings consisting of carbonized sucrose, carbonized polyfurfuryl alcohol, and carbon nanofibers. The coated carbon monoliths were also compared with an integral (composite) carbon monolith. A lipase from Candida antarctica was adsorbed on the monolithic supports. Adsorption on carbon coatings can be very effective, depending on the carbon microstructure. For a high lipase loading. 

Dubmin, MXl, Plavnik, GM., and Zaverina, EJF., Integrated Study of Porous Structure of Activated Carbon ftom Carbonized Sucrose . Carbon, 2,261,1964. 

Figure 3.51 A 2D-HETCOR experiment, (a) 75 MHz spectrum of 1 M sucrose in D2O. (b) 300 MHz H spectrum of 1 M sucrose in D2O. In both spectra the labels G and F refer to the glucose ring and the fructose ring, respectively. Structure of sucrose was given in Fig. 3.25. (c) The 2D-HETCOR spectrum of sucrose. Carbon F2 has no protons directly bonded to it because there is no spot of intensity in the HETCOR plot in line with the F2 chemical shift.

Hierarchical TS-1 MFI TBOT Silica sol Carbon-TPABr Carbon material from sucrose carbonization 170 °C, 7 days Wang, 2011 (19)... 

Ar, C02)-water (Ar, C02)-aqueous solutions (sucrose, carbonate-bicarbonate buffer)... 

Sucrose (table sugar) is the most abundant disaccharide in the biological world. It is obtained principally from the juice of sugarcane and sugar beets. In sucrose, carbon 1 of a-D-glucopyranose is joined to carbon 2 of j8-D-fructofuranose by an a-l,2-glycosidic bond. 

Wang ED, Shi PE, Du CY (2008) Treatment and characterization of gas diffusion layers by sucrose carbonization for PEMFC applications. Electrochem Commun 10 555-558... 

Fig. 4.17 Plot of log,o(n/(mmol g ) against logfo (p7p) for the adsorption of benzene at 20°C on a series of progressively activated carbons prepared from sucrose. (Courtesy Dubinin.)...

A more abundantiy produced substance is ethanol for use in alcohoHc beverages, and as a fuel, solvent, and feedstock for organic syntheses. Ethanol (qv) production from sucrose is carried out in Europe (eg, France and the Netherlands), India, Pakistan, China, and on a very large scale in Brazil, where it is used as a motor fuel. A valuable by-product of ethanol fermentation is industrial CO2 (see Carbon dioxide). 

Berlin Institute Method. This method is for determination of invert sugar in products containing not more than 10% invert in the presence of sucrose. It is a copper reduction method that utilizes MbUer s solution, which contains sodium carbonate. 

Raw juice is heated, treated sequentially with lime (CaO) and carbon dioxide, and filtered. This accomplishes three objectives (/) microbial activity is terminated (2) the thin juice produced is clear and only lightly colored and (J) the juice is chemically stabilized so that subsequent processing steps of evaporation and crystalliza tion do not result in uncontrolled hydrolysis of sucrose, scaling of heating surfaces, or coprecipitation of material other than sucrose. 

Benzoates. The selective debenzoylation of sucrose octabenzoate [2425-84-5] using isopropylamine in the absence of solvents caused deacylation in the furanose ring to give 2,3,4,6,1/3/6 -hepta- and 2,3,4,6,1/6 -hexa-O-benzoyl-sucroses in 24.1 and 25.4% after 21 and 80 hours, respectively (54). The unambiguous assignment of partially benzoylated sucrose derivatives was accompHshed by specific isotopic labeling techniques (54). Identification of any benzoylated sucrose derivative can thus be achieved by comparison of its C-nmr carbonyl carbon resonances with those of the assigned octabenzoate derivative after benzoylation with 10 atom % benzoyl—carbonyl chloride in pyridine. 

Direct halogenation of sucrose has also been achieved using a combination of DMF—methanesulfonyl chloride (88), sulfuryl chloride—pyridine (89), carbon tetrachloride—triphenylphosphine—pyridine (90), and thionyl chloride—pyridine—1,1,2-trichloroethane (91). Treatment of sucrose with carbon tetrachloride—triphenylphosphine—pyridine at 70°C for 2 h gave 6,6 -dichloro-6,6 -dideoxysucrose in 92% yield. The greater reactivity of the 6 and 6 primary hydroxyl groups has been associated with a bulky halogenating complex formed from triphenylphosphine dihaUde ((CgH )2P=CX2) and pyridine (90). 

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