New efficient electrochemical synthesis of 1,5-dithioxylopyranosides in the presence of a sacrificial anode.
Electroreduction of the disulfide derivative RSSR (5, R= [bond]C(6)H(4)[bond]CO[bond]C(6)H(4)[bond]CN) on a mercury pool or a carbon gauze electrode in the presence of 2,3,4-tri-O-acetyl-5-thio-D-xylopyranosyl bromide (1), using a sacrificial zinc anode gave an alpha,beta anomeric mixture of [4-(4-cyanobenzoylphenyl)] 2,3,4-tri-O-acetyl-1,5-dithio-D-xylopyranoside (6) in 40-70% yield, according to the experimental conditions used (nature of solvent, electrolyte salt, and temperature). High selectivity favouring the alpha anomer of 6 is observed starting from the alpha anomer of 1. Mechanistic aspects are discussed.
Brevet
David
D
Laboratoire de Synthèse et d'Electrosynthèse Organometalliques-LSEO-UMR5632, faculté des Sciences Gabriel, 21000 Dijon, France.
Mugnier
Yves
Y
Samreth
Soth
S
Dellis
Philippe
P
D000838:Anions / Q000737:chemistry; D004220:Disulfides / Q000138:chemical synthesis / Q000737:chemistry; D004563:Electrochemistry; D004566:Electrodes; D006031:Glycosylation; D015394:Molecular Structure; D013865:Thioglycosides / Q000138:chemical synthesis* / Q000737:chemistry; D015032:Zinc / Q000737:chemistry
D000838:Anions; D004220:Disulfides; D013865:Thioglycosides; D015032:Zinc