Stereoselective [4+2]‐Cycloaddition with Chiral Alkenylboranes
Stereoselective [4+2]‐Cycloaddition with Chiral Alkenylboranes
复制标题
立体选择性 [4 2] — 与手性烯基硼烷的环加成
DOI：
10.1002/anie.202000652
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发表时间：
2020
期刊：
影响因子：
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通讯作者：
Brown, M. Kevin
中科院分区：
文献类型：
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作者：
Ni, Dongshun;Witherspoon, Brittany P.;Zhang, Hong;Zhou, Chen;Houk, K. N.;Brown, M. Kevin
提出了一种烯基硼烷和二烯的立体选择性[4+2]-环加成反应方法。这一转变是通过引入一种新的战略来实现的，该战略涉及使用手性N-质子化的烯基恶唑硼烷作为亲双烯化合物。该反应导致产物的形成，这些产物可以通过C−B键的立体定向转化，如氧化和同源，容易衍生成更复杂的结构基序。对反应的详细计算评估揭示了反离子对立体选择性的惊人作用。
A method for the stereoselective [4+2]‐cycloaddition of alkenylboranes and dienes is presented. This transformation was accomplished through the introduction of a new strategy that involves the use of chiral N‐protonated alkenyl oxazaborolidines as dieneophiles. The reaction leads to the formation of products that can be readily derivatized to more complex structural motifs through stereospecific transformations of the C−B bond such as oxidation and homologation. Detailed computation evaluation of the reaction has uncovered a surprising role of the counterion on stereoselectivity.