Alpha- and beta-glycosyl sulfonium ions: generation and reactivity.
Low-temperature electrochemical oxidation of thioglycosides gave glycosyl triflates from which glycosyl sulfonium ions were produced (see scheme). The latter were characterized by NMR spectroscopy and cold-spray mass spectrometry as a mixture of alpha- and beta-isomers (45:55). The alpha-glycosyl sulfonium ion exhibited higher reactivity than the beta-glycosyl sulfonium ion in the reaction with methanol, which gave a mixture of alpha- and beta-methyl glycosides (41:59).
Nokami
Toshiki
T
Department of Synthetic Chemistry and Biological Chemistry, Graduate School of Engineering Kyoto University, Nishikyo-ku, Kyoto 615-8510, Japan.
Shibuya
Akito
A
Manabe
Shino
S
Ito
Yukishige
Y
Yoshida
Jun-ichi
J
D003080:Cold Temperature; D004563:Electrochemistry; D005947:Glucose / Q000031:analogs & derivatives / Q000737:chemistry; D006031:Glycosylation; D009682:Magnetic Resonance Spectroscopy; D008698:Mesylates / Q000138:chemical synthesis / Q000737:chemistry; D010084:Oxidation-Reduction; D013452:Sulfonium Compounds / Q000138:chemical synthesis / Q000737:chemistry*; D013865:Thioglycosides / Q000737:chemistry*
D008698:Mesylates; D013452:Sulfonium Compounds; D013865:Thioglycosides; D005947:Glucose