Stereoselective alkoxylation of acyclic precursor, (2S,3S)-2,3-O-isopropylidene-4-chloro-4-phenylthiobutyric acid methyl ester (3) in the presence of SnCl2–AgClO4, followed by Pd(OAc)2 promoted cyclization gave α-l-threofuranosides in good yields.
立体选择性烷氧基化非环状前体 (2S,3S)-2,3-O-异
丙烯基-4-
氯-4-苯
硫丁酸甲酯 (3),在 SnCl2–AgClO4 的存在下进行,然后通过 Pd(OAc)2 催化环化,得到 α-l-三
氟呋喃苷,产率良好。