Organic compounds -- part of the class 532-570 series – Organic compounds – Carbohydrates or derivatives
Patent
1996-06-13
1998-05-05
Kight, John
Organic compounds -- part of the class 532-570 series
Organic compounds
Carbohydrates or derivatives
C08B 3118, C08B 3308, C08B 3508
Patent
active
057476586
DESCRIPTION:
BRIEF SUMMARY
The invention relates to a method for the oxidation of carbohydrates which possess two adjacent secondary alcohol functional groups, wherein a less than equivalent amount of periodate is used and the periodate is regenerated during the reaction.
The oxidation of carbohydrates of this type can lead to dialdehyde carbohydrates. The reactive aldehyde groups render dialdehyde compounds of this type suitable for many applications, for example as cross-linking agents for naturally occurring and synthetic polymers, mainly with the aim of an improvement in the sensitivity to moisture and the production of insoluble films and fibres. Thus, dialdehyde starch is used in the paper, leather and textile industry. It is also usable as an additive in glue, binding agents, coatings, photographic material, thickeners, cosmetics, plastics and the like. An application developed recently is that of carrier material for proteins, for example for use in diagnostics. Cationic dialdehyde starch is also used for the application in paper, in connection with the interaction of the positive (ammonium) groups with the negatively charged cellulose. Furthermore, dicarboxylic acid carbohydrates, which are suitable, inter alia, as calcium-complexing agents (substitutes for phosphate) can be obtained from dialdehyde carbohydrates by further oxidation.
It is known that carbohydrates can be oxidized to dialdehyde carbohydrates using periodic acid or periodate salts, lead(IV) salts or permanganate; the oxidation of inulin with periodate is described, for example, by Maekawa and Nakajima, J. Agr. Chem. Soc. Japan 28, 357-363 (1954) (see Chem. Abs. 10078c (1954)).
The oxidation of carbohydrates with periodate can be represented by the following equation, in which A denotes the residue of a mono-saccharide unit of the carbohydrate. ##STR1##
Instead of the metaperiodate IO.sub.4.sup.- shown in the equation, usually in the form of H.sub.4 IO.sub.6.sup.-, and periodic acid, H.sub.5 IO.sub.6, the oxidizing ion can also be paraperiodate H.sub.2 IO.sub.6.sup.3-.
U.S. Pat. No. 2,648,629 describes a method for the oxidation of polysaccharides by treatment with a catalytic amount (about 0.3 equivalent) of (per)iodic acid, wherein the iodic acid formed is continuously regenerated to periodic acid by means of an electric current passing through the cell which also contains the polysaccharide. Thus, both the oxidation of the polysaccharide and the regeneration of periodate occur in the same reaction chamber, i.e. the anode chamber. The dialdehyde content of the oxidized polysaccharide (starch) is 68-89%. This method is associated with contamination of both the polysaccharide by electrode metal and the electrode by organic material resulting in corrosion of the electrode coating.
U.S. Pat. No. 3,703,508 teaches a method for regenerating spent periodate resulting form the oxidation of polysaccharides, wherein the aqueous liquor containing the spent periodate is separated form the oxidized polysaccharide product, regenerated in a multi-chamber electrodialysis apparatus and then reused for oxidizing a next batch of polysaccharide. A disadvantage of this method is a high (equimolar) consumption of expensive periodate, which becomes very diluted after washing.
A method for the oxidation of starch using an excess of periodate, followed by separation of the reaction product and chemical regeneration of spent periodate using chlorine, was described by McGuire and Mehltretter in Die Starke 23, 42-45 (1971). The dialdehyde content of the oxidized starch is 97%. This method leads to at least equivalent amounts of salts in the end product, which presents separation problems and/or restricts the possible uses of the products.
DD-A-87778 describes a method for the production of water-soluble dialdehyde polysaccharides using electrochemically generated periodate. The water-soluble polysaccharide (dextran) is oxidized with 0.2 equivalent of periodate in order to produce a product having a degree of oxidation of 10%; the reaction mixture is contacted with an ion exchange resi
REFERENCES:
patent: 2648629 (1953-08-01), Dvonch et al.
patent: 3703508 (1972-11-01), Heit et al.
Veelaert et al., "Structural and physico-chemical changes of potato starch along periodate oxidation." Starch, vol. 47: 263-268, 1995.
Van der Zee et al., "Structure-biodegradation relationships of polymeric materials I.--effect of degree of oxidation on biodegradability of carbohydrate polymers." Journal of Environmental Polymer Degradation, vol. 3: 235-242, 1995.
McGuire et al., "Chemical Process for Making Dialdehyde Starch", Die Starke, vol. 23, No. 2, Jan. 1971, pp. 42-45.
The Carbohydrates--Chemistry, Biochemistry, Physiology, (Academic Press Inc., New York), Ed. by Ward Pigman, pp. 346-352, (1957).
Structural Carbohydrate Chemistry, Ed. by E.G.V. Percival, (J. Garnet Miller Ltd., London), pp. 206-208, (1962).
The Introduction to the Chemistry of Carbohydrates, Ed. by Guthrie and Honeyman, (Clarendon Press, Oxford), pp. 72-76, (1964).
Monosaccharides Their Chemistry and Their Roles in Natural Products, Ed. by Collins & Ferrier, (John Wiley & Sons, New York), p. 4, (1995).
De Wit Dirk
Tournois Huibert
Veelaert Sarah
Instituut Voor Agrotechnologisch Onderzoek (ATO-DLO)
Kight John
Lee Howard C.
LandOfFree
Method for the oxidation of carbohydrates does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Method for the oxidation of carbohydrates, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method for the oxidation of carbohydrates will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-56169