An enantiospecific synthesis of (R)-1,4,7-trioxaspiro[5.5]undecane from d-fructose
作者:Kai H. Aamlid、Leslie Hough、Anthony C. Richardson、David Hendry
DOI:10.1016/0008-6215(87)80142-8
日期:1987.7
of four 4-deoxy-1,2- O -ethylene-4-nitrohex-2-uloses having the α- l - xylo , β- d - arabino , α- l - lyxo , and β- d - ribo configurations, together with two heptuloses which arose from products of the incomplete oxidation of the starting material. When nitromethane was in excess of the base used for the cyclisation reaction, the α- l - xylo -hexulose was the major product, but this could be isomerised
摘要1,2-O-乙烯-β-d-果糖吡喃糖的高碘酸氧化和二硝基甲烷与硝基甲烷的闭环反应提供了四种4-脱氧-1,2-O-乙烯-4-硝基己-2-葡萄糖的混合物具有α-1-木糖基,β-d-阿拉伯糖,α-l-lyxo和β-d-核糖基构型,以及由起始原料不完全氧化的产物产生的两个庚糖。当硝基甲烷过量于用于环化反应的碱时,α-1-木糖己糖是主要产物,但是当用过量的甲醇钠处理时,它可以基本上异构化为β-d-核糖异构体。乙酰化α-1-木基-己基吡喃糖,然后还原性消除乙酰氧基,得到(6 R,10 R)-和(6 R,10 S)-10-nitro-1大约1:1的混合物,4,7-三氧杂螺[5.5]十一烷。(6 R,10 S)异构体的酸催化差向异构化得到(6 S,10 S)异构体。在pH 7下用高锰酸盐氧化(6 R,10 R)或(6 R,10 S)异构体可得到十一。用硼氢化钠将其还原,主要得到(6 R,10 S)-1