Oxidation of sucrose

Catalytic oxidation ia the presence of metals is claimed as both nonspecific and specific for the 6-hydoxyl depending on the metals used and the conditions employed for the oxidation. Nonspecific oxidation is achieved with silver or copper and oxygen (243), and noble metals with bismuth and oxygen (244). Specific oxidation is claimed with platinum at pH 6—10 ia water ia the presence of oxygen (245). Related patents to water-soluble carboxylated derivatives of starch are Hoechst s on the oxidation of ethoxylated starch and another on the oxidation of sucrose to a tricarboxyhc acid. AH the oxidations are specific to primary hydroxyls and are with a platinum catalyst at pH near neutraUty ia the presence of oxygen (246,247). Polysaccharides as raw materials ia the detergent iadustry have been reviewed (248). 

Oxidation of Sucrose. Sucrose can be oxidized by HNO, KMnO, and peroxide. Under selected conditions using oxygen with palladium or platinum, the 6- or 6 -hydroxyls can be oxidized to form sucronic acid derivatives (29). 

Balanced equations oxidation of sucrose Ci2H220n(s) + 1202 (g) —> 12C02(g) + 1 lH20(g)... 

SCHEME 40. Hale, Hough, and Richardson s studies on the reductive animation (1988) and Fischer cyclization (1987) of a 3, 4 -dialdehyde derived from lead tetraacetate oxidation of sucrose. The glycosyl morpholines were very sweet ... 

No oxidation products of sucrose other than those produced by degradation have been described. Oxidation of sucrose with periodic acid has been carried out, but neither the method nor the products need to be considered for the present purpose. 

Although many workers have been interested in the production of oxalic acid from sucrose, it is probably true that sucrose cannot compete with other raw materials as a source of this acid. For example, sawdust has been found to be an excellent source of oxalic acid. It is possible, however, to arrest the oxidation of sucrose before the oxalic acid stage is reached and the much more valuable tartaric acid has been obtained in this way. Tartaric acid, at the moment manufactured from waste... 

Platinum supported on carbon (Pt/C) was tested as solid catalysts in the oxidation of sucrose using molecular oxygen as oxidant (Scheme 10). The reaction was carried out in water and under atmospheric pressure. The support strongly influences the reaction and Pt/C was found more efficient than Pt/Alumina at 353 K. Over Pt/C, at a pH of 9, mono-, di-, and tricarboxylate derivatives were mainly obtained with a tricarboxylate yield of 35% [103]. 

In 1994, Kunz et al. studied the oxidation of sucrose in the presence of Pt/C at 307 K and neutral pH [104]. Under these conditions, the positions 6, 6, and V of sucrose were mainly oxidized and a mixture of monocarboxylic and dicarboxylic acids (56/44) has been produced. Note that when the oxidized products were continuously removed by electrodialysis in order to avoid their subsequent... 

Very successful experiments were carried out on the oxidation of sucrose, one mole of which needs three moles of periodic acid, with the formation of one mole each of formic acid and a tetraaldehyde. The latter is oxidized by bromine to a tetracarboxylic acid subsequent acid hydrolysis of the oxygen bridges affords a mixture of acids, all of which were isolated and identified. These results brought in 1943 a confirmation of the structure of sucrose which was discussed, and which gained the approval of C. S. Hudson who, before that, was a little doubtful about the furanoid form of the D-fructosyl group. Similar work was done later with trehalose. In the same way, J. . Courtois obtained confirmation of the structure of raffinose, and established that of stachyose. 

Oxidative bioconversions include notably the oxidation of sucrose to 3-keto-sucrose (Scheme 18),25,203,204,207 a synthon that has been used as starting point for synthesis of many sucrose derivatives (see Sections II.5 and II.8). 

Some microorganisms effect the oxidation of oligosaccharides to glycosid-3-uloses this conversion has been reported for maltose, lactose, and their respective aldobionic acids. Conditions for the oxidation of sucrose by the action of Agrobacterium tumefaciens have been improved and optimized on a molar scale, so that 3-ketosucrose can be produced in 40% yield 449... 

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