Synthesis and [2 + 2] Cycloaddition of Dimethyleneketene Acetals. Reaction with C60 and Facile Hydrolysis of the C-C Bond Connected to C60
Synthesis and [2 + 2] Cycloaddition of Dimethyleneketene Acetals. Reaction with C60 and Facile Hydrolysis of the C-C Bond Connected to C60
复制标题
二亚甲基乙烯酮缩醛的合成和[2 2]环加成。
DOI：
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发表时间：
1994
期刊：
影响因子：
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通讯作者：
E. Nakamura
中科院分区：
文献类型：
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作者：
S. Yamago;Atsuo Takeichi;E. Nakamura
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 products: a type of reaction product previously unavailable. We also found that 3 reacts smoothly with C[sub 60] to give the [2 + 2] adduct 5 and, most remarkably, that the asterisked C[minus]C [sigma] bond in 5 directly connected to the fullerene core is hydrolytically unstable and can be quantitatively cleaved with aqueous acid. 15 refs., 1 tab.
