Synthesis of Diuloses by Chain Elongation of Aldonoyl Chlorides

Article abstract of DOI:10.1002/prac.19983400310

2,3,4,5,6-Penta-O-acetyl-D-galactonic acid chloride (1a) and D-gluconic acid chloride (1b), respectively, react with alkyl acetoacetates and benzoylacetates 2, respectively, to yield derivatives 3 of diuloses with an alkoxycarbonyl group in the branch. Decarboalkoxylation of these compounds gives 1,3-didesoxy-nono-2,4-diuloses 4a,b and 2-deoxy-octo-1,3-diuloses 4c, respectively. Compound 4a and diazomethane react to furnish the corresponding methyl enol ether 5a and 5b.