Activation of Glycosyl Phosphites under Neutral Conditions in Solutions of Metal Perchlorates in Organic Solvents
作者:Heidrun Schene、Herbert Waldmann
DOI:10.1002/(sici)1099-0690(199806)1998:6<1227::aid-ejoc1227>3.0.co;2-4
日期:1998.6
Glycosyl phosphites 1–3 derived from glucose are activated under neutral conditions and without the addition of any further promoter in 1 M solutions of LiClO4, Mg(ClO4)2 or Ba(ClO4)2 in ether, CH2Cl2, or CH3CN and react under these conditions with the alcohols5–9 to give the glycosides 10–14. The best results are obtained in the presence of Ba(ClO4)2. In CH2Cl2 and ether the α-anomers predominate
源自葡萄糖的糖基亚磷酸酯 1-3 在中性条件下被活化,并且在 LiClO4、Mg(ClO4)2 或 Ba(ClO4)2 在乙醚、CH2Cl2 或 CH3CN 中的 1 M 溶液中无需添加任何其他促进剂,并在这些条件下反应条件与醇5-9 得到糖苷10-14。在 Ba(ClO4)2 存在下获得最佳结果。在 CH2Cl2 和醚中,α-异构体占主导地位,在 CH3CN 中,β-异构体过量形成。亚磷酸甲酯 1 和亚磷酸苄酯 3 以 35-66% 的产率提供所需的糖苷,而亚磷酸乙酯 2 是更具反应性的糖基供体,以 62-95% 的产率产生糖苷 10、11 和 13。