Copper-Mediated Fluoroalkylation Reactions with Iododifluoroacetamides: Controlling the Selectivity among Cross-Coupling, Intramolecular Cyclization, and Homocoupling Reactions
Copper-Mediated Fluoroalkylation Reactions with Iododifluoroacetamides: Controlling the Selectivity among Cross-Coupling, Intramolecular Cyclization, and Homocoupling Reactions
复制标题
铜介导的碘二氟乙酰胺氟烷基化反应：控制交叉偶联、分子内环化和均偶联反应的选择性
DOI：
10.1021/jo1005262
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发表时间：
2010-08-20
影响因子：
3.6
通讯作者：
Hu, Jinbo
中科院分区：
文献类型：
--
作者：
Zhu, Jieming;Zhang, Wei;Hu, Jinbo
铜介导的碘代二氟乙酰胺I的氟烷基化反应进行了系统的研究。有人发现，三种类型的反应可能共存于铜介导的碘代二氟乙酰胺和芳基/烯基碘之间的反应：交叉偶联，分子内环化，和homocoupling反应。这三种类型的反应之间的选择性可以通过调节碘二氟乙酰胺的氮原子上的取代基，和/或通过去除交叉偶联反应伙伴（芳基/烯基卤化物）来控制。一般规律如下：（a）在适当的芳基/烯基碘存在下，通常形成交叉偶联产物2（或6）作为主要产物：（B）在不存在芳基/烯基碘的情况下，当R-1 =烷基和R-2 =芳基时，或当R-1 = R-2 =芳基时，可以主要形成分子内环化产物3;和（c）在不存在芳基/烯基碘化物的情况下，当R-1 = R-2 =烷基时，或当R-1 = H且R-2 =烷基、芳基时，可以主要形成同偶联产物4。我们的实验结果还表明，在许多情况下，当交叉耦合，homocoupling，和分子内环化反应共存的铜介导的反应体系中，反应性降低的顺序：交叉耦合>分子内环化> homocoupling。
Cu-mediated fluoroalkylation reactions with iododifluoroacetamides I have been systematically investigated. It was found that three types of reactions may coexist in Cu-mediated reactions between iododifluoroacetamides and aryl/alkenyl iodides: cross-coupling, intramolecular cyclization, and homocoupling reactions. The selectivity among these three types of reactions could be controlled by tuning the substituents on the nitrogen atom of iododifluoroacetamides, and/or by removing the cross-coupling reaction partner (aryl/alkenyl halides). The general rule is as follows: (a) in the presence of proper aryl/alkenyl iodides, the cross-coupling products 2 (or 6) are generally formed as the major products; (b) in the absence of aryl/alkenyl iodides, and when R-1 = alkyl and R-2 = aryl groups, or when R-1 = R-2 = aryl groups, the intramolecular cyclization products 3 can be formed predominantly; and (c) in the absence of aryl/alkenyl iodides, and when R-1 = R-2 = alkyl groups, or when R-1 = H and R-2 = alkyl, aryl groups, the homocoupling products 4 can be formed dominantly. Our experimental results also indicate that in many cases when cross-coupling, homocoupling, and intramolecular cyclization reactions coexist in the Cu-mediated reaction system, the reactivity decreases in the following order: cross-coupling > intramolecular cyclization > homocoupling.