Teaching Aldehydes New Tricks Using Rhodium- and Cobalt-Hydride Catalysis.
Teaching Aldehydes New Tricks Using Rhodium- and Cobalt-Hydride Catalysis.
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DOI：
10.1021/acs.accounts.0c00771
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发表时间：
2021-03-02
影响因子：
18.3
通讯作者：
Dong VM
中科院分区：
文献类型：
--
作者：
Davison RT;Kuker EL;Dong VM
通过使用过渡金属催化剂，化学家们改变了“化学合成的逻辑”，使碳氢键功能化，而碳氢键在传统上被认为是惰性的。在这个框架内，我们的实验室一直着迷于醛C-H键激活的潜力。我们的方法侧重于通过氧化加成甲酰基C-H键来生成酰基金属氢化物，这是1965年由Tsuji首次验证的基本步骤。在本帐户中，我们回顾了我们克服氢酰化限制的努力。最初的研究导致了氢酰化的新变体，并最终刺激了相关转化的发展（例如，碳酰化，环异构化和转移氢甲酰化）。Sakai和他的同事们证实了烯烃的第一次氢化，他们报告说，使用化学计量量的威尔金森催化剂，4-戊烯环化成环戊酮。这一发现引起了人们对氢化的极大兴趣，特别是对环戊酮的对映选择性和催化结构。我们的研究重点是将不对称变体扩展到访问中型环（例如，七元环和八元环）。此外，我们通过将定向基团结合到烯烃伙伴上实现了选择性分子间偶联。在此过程中，我们发现了Rh和Co催化剂，它们可以将二烯醛转化为各种独特的碳环，如环戊酮、双环酮、环己烯醛和环丁酮。基于从烯烃加氢酰化中获得的见解，我们证明了羰基的高度对映选择性加氢酰化。例如，我们证明了酮醛可以环化形成具有高区域和对映体选择性的内酯。在这些报道之后，我们报道了第一个发生高立体控制的分子间例子。酮酰胺经过分子间羰基氢化反应生成含有沉淀肽链的α-酰基氧胺。最后，我们描述了如何转移关键的酰基金属氢化物来实现C-C键的切割过程。转移氢甲酰化使从醛通过去同源化机制制备烯烃成为可能。烯烃受体中环应变的释放为CO和H2的等速转移提供了驱动力。机制研究表明，反离子充当质子穿梭体，使转移氢甲酰化成为可能。总的来说，我们的研究展示了过渡金属催化如何将一个共同的官能团（在这种情况下是醛）转化为结构上不同的基序。调整酰基金属氢化物的配位球可以促进C-C和C-O键的形成反应，以及C-C键的切割过程。
By using transition metal catalysts, chemists have altered the ‘logic of chemical synthesis’ by enabling the functionalization of carbon-hydrogen bonds, which have traditionally been considered inert. Within this framework, our laboratory has been fascinated by the potential for aldehyde C–H bond activation. Our approach focused on generating acyl-metal-hydrides by oxidative addition of the formyl C–H bond, which is an elementary step first validated by Tsuji in 1965. In this Account, we review our efforts to overcome limitations in hydroacylation. Initial studies resulted in new variants of hydroacylation and ultimately spurred the development of related transformations (e.g., carboacylation, cycloisomerization, and transfer hydroformylation). Sakai and coworkers demonstrated the first hydroacylation of olefins when they reported that 4-pentenals cyclized to cyclopentanones, using stoichiometric amounts of Wilkinson’s catalyst. This discovery sparked significant interest in hydroacylation, especially for the enantioselective and catalytic construction of cyclopentanones. Our research focused on expanding the asymmetric variants to access medium-sized rings (e.g., seven- and eight-membered rings). In addition, we achieved selective intermolecular couplings by incorporating directing groups onto the olefin partner. Along the way, we identified Rh and Co catalysts that transform dienyl aldehydes into a variety of unique carbocycles, such as cyclopentanones, bicyclic ketones, cyclohexenyl aldehydes, and cyclobutanones. Building on the insights gained from olefin hydroacylation, we demonstrated the first highly enantioselective hydroacylation of carbonyls. For example, we demonstrated that ketoaldehydes can cyclize to form lactones with high region- and enantioselectivity. Following these reports, we reported the first intermolecular example that occurs with high stereocontrol. Ketoamides undergo intermolecular carbonyl hydroacylation to furnish α-acyloxyamides that contain a depsipeptide linkage. Finally, we describe how the key acyl-metal-hydride species can be diverted to achieve a C–C bond cleaving process. Transfer hydroformylation enables the preparation of olefins from aldehydes by a dehomologation mechanism. Release of ring strain in the olefin acceptor offers a driving force for the isodesmic transfer of CO and H2. Mechanistic studies suggest that the counterion serves as a proton-shuttle to enable transfer hydroformylation. Collectively, our studies showcase how transition metal catalysis can transform a common functional group, in this case aldehydes, into structurally distinct motifs. Fine-tuning the coordination sphere of an acyl-metal-hydride species can promote C–C and C–O bond forming reactions, as well as C–C bond cleaving processes.
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影响因子：
8.4
作者：
Abrams DJ;West JG;Sorensen EJ
通讯作者：
Sorensen EJ
通过钴催化对1,3-二烯的区域选择性水囊化。
影响因子：
15
作者：
Chen, Qing-An;Kim, Daniel K.;Dong, Vy M.
通讯作者：
Dong, Vy M.
影响因子：
15
作者：
Jurkauskas, V;Buchwald, SL
通讯作者：
Buchwald, SL
2005 年至 2015 年立体会聚催化进展：过渡金属介导的立体消融反应、动态动力学分辨率和动态动力学不对称变换。
影响因子：
62.1
作者：
Bhat V;Welin ER;Guo X;Stoltz BM
通讯作者：
Stoltz BM
影响因子：
15
作者：
Coulter, Matthew M.;Kou, Kevin G. M.;Dong, Vy M.
通讯作者：
Dong, Vy M.