A highly chemo- and stereoselectivesynthesis of diethyl (E)-2-(alkylidene)-2-phosphonoacetonitriles via the Knoevenagel condensation reaction of carbonyl compounds with diethyl cyanomethylphosphonate in the presence of zinc chloride has been achieved. By the presented method, various E-isomers of arylmethylidene phosphonates rather than Horner–Wadsworth–Emmons olefination products were obtained in
在氯化锌存在下,通过羰基化合物与氰基甲基膦酸二乙酯的 Knoevenagel 缩合反应,实现了二乙基 ( E )-2-(亚烷基)-2-膦酰基乙腈的高度化学和立体选择性合成。通过所提出的方法,芳基亚甲基膦酸酯的各种E异构体而不是 Horner-Wadsworth-Emmons 烯化产物以良好至优异的产率获得。它们的E构型由 X 射线衍射和 NMR 分析确定。此外,DFT 计算提供了对反应的化学和立体选择性的见解。
Shen, Yanchang; Jiang, Guo-Fang, Journal of Chemical Research - Part S, 2000, # 3, p. 140 - 141
作者:Shen, Yanchang、Jiang, Guo-Fang
DOI:——
日期:——
A Highly Stereoselective Knoevenagel Reaction of<i>N</i>-Tosylimines with Active Methylene Compounds in DMSO
作者:Ryoichi Chiba、Takeshi Oriyama
DOI:10.1246/cl.2008.1218
日期:2008.12.5
In the presence of molecular sieves (MS) 4A in dimethyl sulfoxide (DMSO), a highly stereoselective Knoevenagel reaction of various N-tosylimines with activemethylenecompounds proceeded smoothly, producing the corresponding Knoevenagel products in high to excellent yields.