作者:Richard H. Furneaux、Graeme J. Gainsford、Fred Shafizadeh、Thomas T. Stevenson
DOI:10.1016/0008-6215(86)85029-7
日期:1986.1
Acetylation, hydrogenolytic debenzylation, and pyridinium chlorochromate oxidation then led to the 2- O -acetyl-1,6-anhydro-hexos-4-uloses, from which 3 was obtained by tetraethylammonium acetate-catalyzed β-elimination of acetic acid. On sealed-tube thermolysis in the range of 210–260°, 3 generated 3-oxidopyrylium by loss of formaldehyde; this ylide was efficiently trapped by unreacted 3 , to yield
摘要用左旋葡糖醛酮(2)分六步合成了异戊葡糖醛酮(1,6-脱水-2,3-二脱氧-β-d-甘油-hex-2-enopyranos-4-ulose,3)。因此,用硼氢化钠还原通过将苄醇加成2而获得的1,6-脱水-4-O-苄基-3-脱氧-β-d-赤-己基吡喃并-2-ulose,得到硼氢化钠,得到可分离的混合物。的C-2差向异构醇1,6-脱水-4-O-苄基-3-脱氧-β-d-阿拉伯糖-和-核糖-六吡喃糖,两者均显示出分子内氢键。然后乙酰化,氢解脱苄基化和吡啶鎓氯铬酸盐的氧化产生2-O-乙酰基-1,6-脱水-己基-4-uloses,通过乙酸四乙铵催化的β-消除反应从中获得3。在210-260°的密封管热解中,3会由于甲醛的流失而产生3-氧化op;该叶立德被未反应的3有效捕获,得到[4π+ 2π] -1,3-偶极环加合物14和15。通过X射线晶体学研究充分阐明了14的结构。在酸催化的纤维素热解产物中,未检出3或加合物14和15。