An unusual reaction of 1,6-anhydroaldohexopyranose derivatives leading to glycals
作者:Prakash Bhaté、Derek Horton
DOI:10.1016/0008-6215(85)90019-9
日期:1985.6
Treatment of a solution of the 2-O-(N,N-dimethylsulfamoyl) derivative 3 of the levoglucosenone-derived carbocycle 1 in liquid ammonia at -40 to -50 degrees with sodium metal gave 73% of the glycal derivative 4 instead of the expected 2-deoxy derivative (2) of 1. Under the same conditions, the 2-O-(N,N-dimethylsulfamoyl) derivatives of 1,6-anhydro-3,4-dideoxy-4-C-methyl-beta-D-ribo- and -arabino-hexopyranoses
用钠金属在液氨中以-40至-50度处理左葡萄糖葡萄糖酮衍生的碳环1的2-O-(N,N-二甲基氨磺酰基)衍生物3在液氨中的溶液,得到73%的糖基衍生物4,而不是预期的1的2-脱氧衍生物(2)。在相同条件下,1,6-脱水-3,4-二脱氧-4-C-甲基-β-的2-O-(N,N-二甲基氨磺酰基)衍生物乙酰化后,D-核糖和阿拉伯糖基六吡喃糖产生70%的6-O-乙酰基-1,5-脱水-2,3,4-三苯氧基-4-C-甲基-D-赤藓基-己糖-1 -enol。相反,从1,6-脱水-3,4-O-异亚丙基-β-D-半乳糖和-talo-吡喃糖获得的2-(N,N-二甲基-氨基磺酸盐)得到6-O-乙酰基-1。 ; 5-5-脱水-2-脱氧-3,4-O-异亚丙基-D-lyxo-hex-1-enit ol的收率很低;C-3处的氧基取代基可能会干扰导致糖基化的反应。