Thermal Degradation of Designed Carbohydrate N-Oxides: A Single Methodology for the Synthesis of Ketoses, Enol Ethers, and Branched-Chain Sugars from N-Oxides Derived from d-Altrose Aminosugars
Thermal Degradation of Designed Carbohydrate N-Oxides: A Single Methodology for the Synthesis of Ketoses, Enol Ethers, and Branched-Chain Sugars from N-Oxides Derived from d-Altrose Aminosugars
corresponding allylethers. Oxidation of the allylethers, followed by thermal elimination and rearrangement, gave C -allylhexosuloses in good yield. Rearrangement of ethers 10a and 10c was especially stereoselective, giving axially oriented C -allylhexosulose derivatives, which were readily epimerized to their equatorial isomers in quantitative yield. In the Claisenrearrangement of the crotyl ether 14c ,