Stereo- and regio-selectivity of diethylaminosulfur trifluoride as a fluorinating reagent for methyl glycosides
作者:Chandrasiri W. Somawardhana、Eric G. Brunngraber
DOI:10.1016/0008-6215(83)84005-1
日期:1983.9
Methyl glycopyranosides reacted with diethylaminosulfur trifluoride (DAST) in the absence of solvent to yield methyl dideoxy-difluoro and deoxy-fluoro glycopyranosides. Methyl alpha-D-glycopyranosides produced 6-deoxy-6-fluoro- and 4,6-dideoxy-4,6-difluoro derivatives with Walden inversion at C-4. Methyl beta-D-glucopyranoside also produced a 3,6-dideoxy-3,6-difluoro derivative, with Walden inversion
在没有溶剂的情况下,甲基吡喃葡萄糖苷与二乙基氨基三氟化硫(DAST)反应,生成甲基双脱氧二氟和脱氧氟吡喃葡萄糖苷。甲基α-D-吡喃葡萄糖苷产生6-脱氧-6-氟-和4,6-二脱氧-4,6-二氟衍生物,在C-4处有沃尔登反型。甲基β-D-吡喃葡萄糖苷也产生了3,6-dideoxy-3,6-difluoro衍生物,在C-3处有Walden倒置。甲基6-O-三苯甲基-α-D-吡喃葡萄糖苷与DAST反应生成相应的4-脱氧-4-氟吡喃半乳糖苷衍生物。