A one-pot regioselective heterofunctionalization of 1,2-O-isopropylidene-α-D-xylofuranose (1) and 1,2-O-isopropylidene-α-D-ribofuranose (2) with zinc azide, zinc thiocyanate or zinc N,N-dimethyldithiocarbamate via the Mitsunobu reaction has been performed. With 2, the reaction gave selectively the desired products substituted at C-5 in good isolated yields (60-65%). However, application of the same reaction conditions to 1 led to the predominant formation of a cyclic 3,5-anhydro derivative. In contrast, the reaction of hydrazoic acid with 1 afforded 5-azido-5-deoxy-1,2-O-isopropylidene-α-D-xylofuranose besides formerly unknown 5-azido-3,5-dideoxy-1,2-O-isopropylidene-α-D-glycero-pent-3-enofuranose and 3,5-diazido- 3,5-dideoxy-1,2-O-isopropylidene-α-D-ribofuranose; the yields depended on the reaction time and the molar ratio of reagents.
一锅法的选择性杂功能化反应已经用
锌叠氮化物、
硫氰酸锌或
锌N,N-
二甲基二硫代
氨基甲酸酯通过Mitsunobu反应成功地对1,2-O-异丙基-α-
D-木糖呋喃糖(1)和1,2-O-异丙基-α-
D-核糖呋喃糖(2)进行了。对于2,反应在C-5位置选择性地给出了所需产物,且收率良好(60-65%)。然而,将相同的反应条件应用于1,则主要形成了环状3,5-缩
水衍
生物。相反,将
叠氮酸与1反应得到了5-
叠氮基-5-去氧-1,2-O-异丙基-α-
D-木糖呋喃糖,以及前所未知的5-
叠氮基-3,5-二去氧-1,2-O-异丙基-α-D-
甘油-3-烯酮
呋喃糖和3,5-二
叠氮基-3,5-二去氧-1,2-O-异丙基-α-
D-核糖呋喃糖;产率取决于反应时间和试剂的摩尔比。