Synthesis and [2 + 2] Cycloaddition of Dimethyleneketene Acetals. Reaction with C60 and Facile Hydrolysis of the C-C Bond Connected to C60
作者:Shigeru Yamago、Atsuo Takeichi、Eiichi Nakamura
DOI:10.1021/ja00082a041
日期:1994.2
We report here that the O-alkylated enolates of cyclopropanecarboxylates (dimethyleneketene acetals 3) can be prepared from readily available precursors, and that they are extemely reactive, serving as useful surrogates of the elusive parent enolates. Their utility is illustrated by the [2 + 2] cycloaddition to electron-deficient olefins, which, after hydrolytic workup, gives rise to the Michael addition
我们在此报告,环丙烷羧酸酯(二亚甲基乙烯酮缩醛 3)的 O-烷基化烯醇化物可以从容易获得的前体制备,并且它们具有极强的反应性,可作为难以捉摸的母体烯醇化物的有用替代物。它们的效用通过对缺电子烯烃的 [2 + 2] 环加成来说明,在水解后,产生迈克尔加成产物:一种以前无法获得的反应产物。我们还发现 3 与 C[sub 60] 顺利反应得到 [2 + 2] 加合物 5,最显着的是,直接连接到富勒烯核的 5 中带星号的 C[minus]C[sigma] 键是水解的不稳定,可用酸水溶液定量裂解。15 个参考文献,1 个标签。