Selective Amine Cross-Coupling Using Iridium-Catalyzed "Borrowing Hydrogen" Methodology
Selective Amine Cross-Coupling Using Iridium-Catalyzed "Borrowing Hydrogen" Methodology
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DOI：
10.1002/anie.200904028
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发表时间：
2009-01-01
影响因子：
16.6
通讯作者：
Williams, Jonathan M. J.
中科院分区：
文献类型：
--
作者：
Saidi, Ourida;Blacker, A. John;Williams, Jonathan M. J.
胺在医药、农用化学品、染料和聚合物等方面有着广泛的应用特别是胺的烷基化，特别是单烷基化的控制，引起了相当大的关注虽然烷基卤化物是传统的胺烷化剂，但它们可能是有毒和致突变的。作为一种替代方法，已经使用各种过渡金属催化剂实现了胺与醇的烷基化反应自从第一个使用均相催化剂的反应以来，[4]几个基团，[5]包括我们自己的，[6]已经报道了能够使用醇实现胺烷基化的过渡金属催化剂；Fujita， Yamaguchi和同事有一篇关于使用[{Cp* IrCl2} 2]（Cp*=五甲基环戊二烯基）进行烷基化反应的报告。[7]过渡金属催化的胺的烷基化反应也有报道，[8]虽然RNH2和R ' nh2两种胺的偶联，但通常会产生包括R2NH， RR ' nh和R ' 2NH的混合物。最近，Beller和他的同事已经证明，钌基的Shvo催化剂可以用于当一种胺组分（即苯胺和叔烷基胺）无法氧化时实现选择性胺偶联胺的偶联可以考虑通过方案1中概述的“借氢”途径进行。
Amines have widespread importance with applications as pharmaceuticals, agrochemicals, dyes, and polymers.[1] In particular, the alkylation of amines has raised considerable attention, especially the control of monoalkylation.[2] Whilst alkyl halides are traditional alkylating agents for amines, they can be toxic and mutagenic. As an alternative, the alkylation of amines by alcohols has been achieved using various transition-metal catalysts.[3] Since the first examples of this reaction using homogeneous catalysts,[4] several groups,[5] including our own,[6] have reported transition-metal catalysts capable of achieving amine alkylation using alcohols; there is a report from Fujita, Yamaguchi, and co-workers on the use of [{Cp* IrCl2} 2](Cp*= pentamethylcyclopentadienyl) for this alkylation reaction.[7]The transition-metal-catalyzed alkylation of amines by amines has also been reported,[8] although the coupling of two amines, RNH2 and R’NH2, generally leads to a mixture of products including R2NH, RR’NH, and R’2NH. Recently, Beller and co-workers have demonstrated that the ruthenium-based Shvo catalyst can be used to effect selective amine coupling when one amine component is unable to undergo oxidation (ie, anilines and tert-alkylamines).[9] The coupling of amines can be considered to proceed by the “borrowing hydrogen” pathway outlined in Scheme 1.