D-alal是通过使用NaBH4CeCl3 x 7 H2O系统还原大体积的甲硅烷基保护的1,5-脱水己基-1-en-3-uloses选择性获得的。该合成的关键点是保护基团的性质。当使用大体积的甲硅烷基如叔丁基二苯基甲硅烷基作为底物时,以> 99%的选择性获得了受保护的D-alal。相反,当使用乙酰化的烯酮时,仅获得保护的D-葡萄糖。还发现添加CeCl3 x 7 H2O会影响选择性。
Efficient Synthesis of Rare Sugar <scp>d</scp>-Allal via Reversal of Diastereoselection in the Reduction of Protected 1,5-Anhydrohex-1-en-3-uloses: Protecting Group Dependence of the Stereoselection
作者:Takashi Fujiwara、Masahiko Hayashi
DOI:10.1021/jo801596q
日期:2008.11.21
loses using the NaBH4CeCl3 x 7 H2O system. The crucial point of this synthesis is the nature of the protectinggroup. When bulky silyl group such as t-butyldiphenylsilyl was used as substrate, protected D-allal was obtained in >99% selectivity. In contrast, when acetylated enone was used, protected D-glucal was obtained exclusively. The addition of CeCl3 x 7 H2O was also found to influence selectivity
D-alal是通过使用NaBH4CeCl3 x 7 H2O系统还原大体积的甲硅烷基保护的1,5-脱水己基-1-en-3-uloses选择性获得的。该合成的关键点是保护基团的性质。当使用大体积的甲硅烷基如叔丁基二苯基甲硅烷基作为底物时,以> 99%的选择性获得了受保护的D-alal。相反,当使用乙酰化的烯酮时,仅获得保护的D-葡萄糖。还发现添加CeCl3 x 7 H2O会影响选择性。