Anion radical chain cycloaddition of tethered enones: Intramolecular cyclobutanation and Diels-Alder cycloaddition
Anion radical chain cycloaddition of tethered enones: Intramolecular cyclobutanation and Diels-Alder cycloaddition
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DOI：
10.1021/ol0172065
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发表时间：
2002-02-21
期刊：
影响因子：
5.2
通讯作者：
Krische, MJ
中科院分区：
文献类型：
--
作者：
Roh, Y;Jang, HY;Krische, MJ
[图解]观察到阴极还原生成的某些双烯酮的阴离子自由基参与分子内的环丁烷化反应，通过阴离子自由基链机制生成双环[3.2.0]庚烷衍生物。给出了涉及远端阴离子自由基中间体的逐步环加成反应的证据。除了新的阴离子自由基环丁烷基化，还观察到了一种前所未有的分子内阴离子自由基饮食-Alder产品。讨论了与钴催化的双烯酮环丁烷化反应在底物范围内的平行趋势。
[GRAPHICS]The anion radicals of certain bis(enones), generated by cathodic reduction, are observed to participate in intramolecular cyclobutanation, yielding bicyclo[3.2.0]heptane derivatives through an anion radical chain mechanism. Evidence for stepwise cycloaddition involving distonic anion radical intermediates is presented. In addition to the novel anion radical cyclobutanations, an unprecedented intramolecular anion radical Diets-Alder product is observed. Parallel trends in substrate scope vis-a-vis the Co-catalyzed bis(enone) cyclobutanation are discussed.