Synthesis of α,β-unsaturated, carbonyl sugar derivatives by methyl sulfoxide oxidation and elimination
作者:D.M. Mackie、A.S. Perlin
DOI:10.1016/s0008-6215(00)82260-0
日期:1972.9
Abstract Oxidation of some partially O -acylated sugar derivatives with methyl sulfoxide in the presence of sulfur trioxide and triethylamine is described. With a few exceptions, compounds possessing a free primary, secondary, or anomeric hydroxyl group are smoothly oxidized, and when an acyloxy group is suitably situated α,β elimination also occurs. The last conditions have permitted the synthesis
摘要描述了在三氧化硫和三乙胺存在下,用甲基亚砜氧化部分被O-酰化的糖衍生物的方法。除少数例外,具有游离伯,仲或异头羟基的化合物会被平滑氧化,并且当适当地放置酰氧基时,也会发生α,β消除。最后的条件允许合成多种α,β不饱和羰基化合物,即4-deoxy-6-aldelrydo-L-threo -hex-4-enodialdo-1,5-pyranose的衍生物,其L-erythro类似物和3-脱氧糖-2-enono-1,5-内酯。看来α-苏式和α-赤型异构体采用该构象,而β-苏式和β-赤藓醇型异构体采用该构型,并且端基异构化作用对这些趋势起重要作用。氧化消除顺序的总速率和程度在很大程度上取决于三氧化硫和三乙胺的浓度,以及试剂的混合顺序。在选择的反应条件下,该速率对羟基的位置以及所消除的质子和酰氧基的初始相对位置不敏感。尽管在某些情况下很容易消除苯甲酰氧基(但不是苄氧基),但在其他情况下则不能进行