Catalytic Hydrothiolation: Counterion-Controlled Regioselectivity.
Catalytic Hydrothiolation: Counterion-Controlled Regioselectivity.
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DOI：
10.1021/jacs.8b11395
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发表时间：
2019-02
影响因子：
15
通讯作者：
Xiao-Hui Yang;Ryan T Davison;Shao-Zhen Nie;F. Cruz;Tristan M McGinnis;V. Dong
中科院分区：
文献类型：
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作者：
Xiao-Hui Yang;Ryan T Davison;Shao-Zhen Nie;F. Cruz;Tristan M McGinnis;V. Dong
在这篇文章中，我们扩大了催化氢硫醇的1，3-二烯，以获得烯丙基或高烯丙基硫化物与高区域控制。机制研究支持的途径，其中区域选择性是由与Rh中心相关的counterpartial的选择。非配位的抗衡离子，如SbF 6-，允许η4-二烯配位到Rh络合物，并导致烯丙基硫化物。相反，配位抗衡离子，如Cl-，有利于中性Rh络合物，其中二烯结合η2以提供高烯丙基硫化物。我们提出的机制，合理的分数依赖于硫醇的1，2-Markovnikov氢硫醇化，而占反向依赖于硫醇的3，4-抗Markovnikov途径。通过精油（β-法尼烯）的巯基化反应，首次实现了（-）-agelasidine A的对映选择性合成。
In this Article, we expand upon the catalytic hydrothiolation of 1,3-dienes to afford either allylic or homoallylic sulfides with high regiocontrol. Mechanistic studies support a pathway in which regioselectivity is dictated by the choice of counterion associated with the Rh center. Non-coordinating counterions, such as SbF6-, allow for η4-diene coordination to Rh complexes and result in allylic sulfides. In contrast, coordinating counterions, such as Cl-, favor neutral Rh complexes in which the diene binds η2 to afford homoallylic sulfides. We propose mechanisms that rationalize a fractional dependence on thiol for the 1,2-Markovnikov hydrothiolation while accounting for an inverse dependence on thiol in the 3,4- anti-Markovnikov pathway. Through the hydrothiolation of an essential oil (β-farnesene), we achieve the first enantioselective synthesis of (-)-agelasidine A.