Peracetylated 1,6-dibromo-d-glucitol as efficient precursor of 1,6-diiodo and some mono-, disubstituted and heterocyclic d-glucitol derivatives
作者:Sami Halila、Mohammed Benazza、Gilles Demailly
DOI:10.1016/s0008-6215(02)00421-4
日期:2003.1
regioselectivity allowed the synthesis of some mono- and disubstituted derivatives of D-glucitol. Thus, the peracetylated derivatives of D-glucitol, 6-bromo, 6-bromo-1-S-butyl, 6-bromo-1-S-octyl, 6-S-butyl, 6-S-butyl-1-S-octyl, 1-S-butyl, 1,6-di-S-octyl and 6-S-phenyl were synthesised in good to excellent yields. With S= as binucleophilic reagent, 1a gave mainly the thiepane derivative (75%) plus the 1-S-acetyl-2
由D-葡萄糖醇获得的2,3,4,5-四-O-乙酰基-1,6-二溴-1,6-二脱氧-D-葡萄糖醇(1a)容易转化为1,6-二碘衍生物与过量的碘化钠在丁酮中回流2小时反应,收率(97%)。当反应时间延长至24 h并且粗产物被乙酰化时,分离出1,2,3,4,5-戊五-O-乙酰基-6-脱氧-6-碘-D-葡萄糖醇和D-葡萄糖醇六乙酸酯分别达到50%和26%的产量。然后在C-1区域选择性地进行单脱卤。这种区域选择性允许合成D-葡萄糖醇的一些单取代和二取代的衍生物。因此,D-葡萄糖醇,6-溴,6-溴-1-S-丁基,6-溴-1-S-辛基,6-S-丁基,6-S-丁基-1-S-的全乙酰化衍生物。合成了辛基,1-S-丁基,1,6-二-S-辛基和6-S-苯基,收率良好。