Total Synthesis of 2-Isocyanoallopupukeanane: Construction of Caged Skeleton by Intramolecular Alkylation of Bromonitriles
Total Synthesis of 2-Isocyanoallopupukeanane: Construction of Caged Skeleton by Intramolecular Alkylation of Bromonitriles
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DOI：
10.1021/acs.orglett.2c02434
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发表时间：
2022-08-26
期刊：
影响因子：
5.2
通讯作者：
Tanino，Keiji
中科院分区：
文献类型：
--
作者：
Kato，Kosuke;Ikeuchi，Kazutada;Tanino，Keiji
通过含腈侧链的环己酮衍生物的分子内烷基化反应，发展了一种构建双环[3.2.1]辛烷骨架的新方法。通过4-取代环己酮的三异丙基硅烯醇醚的立体选择性溴化反应制备了环化前体。在用LiNEt 2处理后，溴腈进行立体选择性分子内SN 2反应，得到凸面上具有氰基的双环[3.2.1]辛烷衍生物。以甲基乙烯基酮为起始原料，经17步转化反应，合成了2-异氰基别基庚烷，产率6.5%。
A new method for constructing the bicyclo[3.2.1]octane skeleton was developed by the intramolecular alkylation of a nitrile-side-chain-containing cyclohexanone derivative. The cyclization precursors were prepared via the stereoselective bromination of the triisopropylsilyl enol ethers of 4-substituted cyclohexanones. Upon treatment with LiNEt2, the bromonitriles underwent a stereoselective intramolecular SN2 reaction to afford bicyclo[3.2.1]octane derivatives with a cyano group on the convex face. The total synthesis of 2-isocyanoallopupukeanane (6.5% yield) from methyl vinyl ketone was accomplished via a 17-step transformation.