Chapter 27: Sodium D-galactonate, D-Galactono-1,4-lactone, and synthetically useful methyl D-galactonates By Verónica Rivas, Adriana A. Kolender, Oscar Varela, and Gilbert Duhirwe

RIVAS, M. VERÓNICA; KOLENDER, ADRIANA A.; VARELA, OSCAR; GILBERT DUHIRWE

JOURNAL OF CARBOHYDRATE CHEMISTRY

TAYLOR & FRANCIS INC

Año: 2018 vol. 37

0732-8303

D-Galactono-1,4-lactone (3) is a useful chiral-starting material for the synthesisof various molecules. For example, hex-2-enono-1,4-lactones (furan-2-ones)have been obtained by prolonged benzoylation of 3. Diunsaturated or monounsaturatedlactone derivatives can be formed, depending on the substitution patternand reaction conditions. Hydrogenation of a diunsaturated product affordeda racemic 3,5-dideoxylactone derivative, while hydrogenation of a per-O-acylatedaldonolactone in the presence of Et3N gave a 3-deoxy derivative, via a β-elimination/hydrogenation process. Bromination of 3 with HBr/AcOH and subsequentper-O-acetylation afforded the 6-bromo-6-deoxy per-O-acetylated lactone.Similar to the enonolactones, hydrogenolysis of the bromides yielded also deoxylactones.Therefore, combination of β-elimination and bromination reactions, followedby hydrogenolysis, have been applied for the synthesis of polydeoxygenatedlactones, which are precursors of rare deoxy sugars such as 3,6-dideoxy-D-xylohexose(abequose).