Reaction of Enohexopyranoside Acetates with Lithium Dimethylcuprate(I) and Its Application to Synthesis of Prelog-Djerassi Lactone
作者:Nobuya Kawauchi、Hironobu Hashimoto
DOI:10.1246/bcsj.60.1441
日期:1987.4
In the reaction of two 2-O-acetyl-3-enohexopyranosides and four 4-O-acetyl-2-enohexopyranosides including 2-C-methyl and 4-C-methyl derivatives, respectively, with lithium dimethylcuprate(I), anti SN2′ substitution was proved to be preferential, giving the corresponding C-methylated derivatives. On the other hand, SN2 substitution occurred in the reaction of the 2-enopyranoside without methyl branch
在两种 2-O-acetyl-3-enohexopyranosides 和包括 2-C-methyl 和 4-C-methyl 衍生物的四种 4-O-acetyl-2-enohexopyranosides 分别与二甲基铜酸锂(I)反应时,抗 SN2 '取代被证明是优先的,得到相应的C-甲基化衍生物。另一方面,SN2取代发生在无甲基支链的2-烯吡喃糖苷与D-葡萄糖三乙酸酯的反应中。