| TUD Organische Chemie | | Immel | | Publications | | Papers | | Abstract 02 | | | View or Print (this frame only) |
Frieder W. Lichtenthaler, Stefan Immel, Dierk Martin, and Volkhard Müller
Starch/Stärke 1992, 44, 445-456.
The utilization of inexpensive, bulk-scale accessible, renewable disaccharides as organic raw materials necessitates their practice-oriented conversion into products with different functional groups and, hence, broader application profiles. The backlog for the development of practical reaction channels to versatile building blocks from disaccharides being particularly obvious. Correspondingly this account describes a series of examples by which the reaction potential inherent in disaccharides such as sucrose, lactose, maltose, and isomaltulose is utlizied towards the acquisition of versatile building blocks without cleaving the intersaccharidic linkage. - The glucose portion of sucrose, e.g. can be converted into dihydropyranones with the carbonyl function either at C-2 or C-4, the reducing parts of maltose and lactose may be transformed into enediolone or enollactone structures, whilst the fructose moiety of isomaltulose elaborates a furan ring by threefold, acid-induced elimination of water to yield the O-glucosylated HMF, i.e. glucosyloxymethyl-furan-2-carboxaldehyde. - All reaction sequences comply with criteria of practicality and therefore being transformable to large-scale without major changes. Another novel entry reaction into O-functionalized disaccharide derivatives, the cathodic deprotonation and subsequent trapping of the mono-anion of sucrose with suitable reagents according to Hamann, was evaluated in terms of understanding the regioselectivity attainable through computer simulations of relevant conformers of sucrose in solution, and the corresponding molecular electrostatic potential (MEP) profiles.
Additional Graphics: Sucrose