Abstract The reaction between dialkyl acetylene dicarboxylate and 2-aryl-1,3-dioxane-4,6-dione derivatives in the presence of triphenylphosphine in ethyl acetate led to stable phosphorus ylides in good yields. These stabilized phosphorus ylides exist as a mixture of two geometrical isomers as a result of restricted rotation around the carbon–carbon partial double bond. The 1H NMR variable temperature spectra
摘要
乙炔二
羧酸二烷基酯与 2-芳基-1,3-
二恶烷-4,6-二酮衍
生物在
三苯基膦存在下在
乙酸乙酯中的反应以良好的收率得到稳定的
磷叶立德。由于围绕碳-碳部分双键的旋转受限,这些稳定的
磷叶立德以两种几何异构体的混合物形式存在。研究了 3c 的 1H NMR 变温光谱并报告了结果。图形概要