Selectively tosylated aldonolactones as precursors for highly functionalized, enantiomerically pure tetrahydrofurans
作者:Holger Frank、Inge Lundt
DOI:10.1016/0040-4020(95)00199-i
日期:1995.5
α,ω-Di-O-tosylated-aldonolactones were selectively converted into functionalized tetrahydrofurans when boiled in water-dioxane. Thus, the 2,7-di-O-tosyl-D-glycero-D-gulo-heptono-1,4-lactone (1) readily gave the 2,5;4,7-di-anhydride with inversion of the configuration at C-2, while the 2,6-di-O-tosylated hexonolactones with D-talo -(2)- and D- manno- (3) configurations gave the 2-O-tosylated 3,6-anhydrides
α,ω -二ö -tosylated-aldonolactones在水-二恶烷煮沸时被选择性地转化成官能四氢呋喃。因此,2,7-二-O-甲苯磺酰基-D-甘油-D-古洛糖醇-庚内酯-1,4-内酯(1)容易得到2,5; 4,7-二酐,但构型相反在C-2处,而具有D- talo-(2)-和D- manno-(3)构型的2,6-二-O-甲苯磺酸化己内酯给出了2 - O-甲苯磺酸化3,6-酐7和9, 分别。最后,在更慢的反应中,2 - O-甲苯磺酸-L-鼠李糖-1,4-内酯(4)提供了在C-2处反转的2,5-酸酐10作为唯一产物。