Regio- and stereoselective anomeric esterification of glucopyranose 1,2-diols and a facile preparation of 2-O-acetylated glucopyranosyl trichloroacetimidates from the corresponding 1,2-diols.
A highly regio- and stereoselective anomeric esterification of 3-O-allyl (or benzyl, or benzoyl)-4,6-O-isopropylidene-alpha,beta-d-glucopyranose with acetyl chloride, or allyl chloroformate, or ethyl chloroformate gave the corresponding 2-OH, 1-beta-acetates or -carbonates in excellent yields. The 2-OH, 1-beta-acetates were readily converted to the corresponding 2-O-acetylated glucopyranosyl trichloroacetimidates by reaction with trichloroacetonitrile via base promoted acetyl migration, while the 2-OH, 1-beta-carbonates were good glycosyl acceptors for the synthesis of (1-->2)-linked oligosaccharides.
Zhang
Jianjun
J
Key Lab of Pesticide Chemistry and Application Technology, Department of Applied Chemistry, China Agricultural University, Beijing 100094, China.
Liang
Xiaomei
X
Wang
Daoquan
D
Kong
Fanzuo
F
D000085:Acetates / Q000737:chemistry; D000097:Acetonitriles / Q000737:chemistry*; D002236:Carbohydrate Conformation; D002712:Chlorides / Q000737:chemistry; D004951:Esterification; D005561:Formates / Q000737:chemistry; D005563:Formic Acid Esters / Q000737:chemistry; D008956:Models, Chemical; D015394:Molecular Structure; D009844:Oligosaccharides / Q000138:chemical synthesis* / Q000737:chemistry*; D013237:Stereoisomerism
D000085:Acetates; D000097:Acetonitriles; D002712:Chlorides; D005561:Formates; D005563:Formic Acid Esters; D009844:Oligosaccharides; C007658:ethyl chloroformate; C029549:trichloroacetonitrile; C042113:allyl chloroformate; C081124:acetyl chloride