Cooperative Catalysis of Combined Systems of Transition-Metal Complexes with Lewis Acids: Theoretical Understanding
Cooperative Catalysis of Combined Systems of Transition-Metal Complexes with Lewis Acids: Theoretical Understanding
复制标题
DOI：
10.1002/tcr.201600086
复制
发表时间：
2016-10-01
期刊：
影响因子：
6.6
通讯作者：
Sakaki, Shigeyoshi
中科院分区：
文献类型：
--
作者：
Guan, Wei;Zeng, Guixiang;Sakaki, Shigeyoshi
过渡金属络合物与Lewis酸的结合最近被应用于几个催化反应，其中Lewis酸作为一种非无害的添加剂起着关键的加速反应的作用。本文根据我们最近的理论研究，讨论了路易斯酸加速反应的原因。在镍(0)-硼烷络合物对二氢分子的H-H sigma键活化过程中，硼烷部分的空p轨道与H-H sigma键MO相互作用，形成电荷转移(CT)从二氢分子到硼烷部分，从而加速反应。在铂(0)-双膦配合物激活BF3的B-F sigma键过程中，第二个BF3分子与从B原子解离的F原子相互作用，稳定了从F原子到第二个BF3原子的过渡态和产物。在该反应中，底物BF3作为Lewis酸起到了关键作用，加速了B-F sigma键的活化。在镍催化的芳基羧基苯甲腈与乙炔的脱氰化偶联反应中，两个路易斯酸铝分子与底物的氰基N原子和羰基O原子相互作用，稳定了过渡态和中间体。在镍催化的芳香酰胺与烯烃的烷基化反应中，Lewis酸通过与羰基O原子相互作用提高了烷基化反应的对位选择性。在镍催化的Sp(3)碳和Sp碳原子与二氧化碳的羧化反应中，Lewis酸通过与二氧化碳的O原子相互作用，加速了二氧化碳插入金属碳键的反应，而不是Sigma键的活化，这是因为相互作用提高了金属碳键到二氧化碳的CT。这一理论知识表明，过渡金属络合物与Lewis酸的结合可以拓宽过渡金属络合物作为催化剂的应用范围。
The combination of transition-metal complexes and Lewis acids has been recently applied to several catalytic reactions, in which the Lewis acid plays a crucial role as a non-innocent additive to accelerate the reaction. In this review article, the reasons for the acceleration by the Lewis acid are discussed based on our recent theoretical studies. In the H-H sigma-bond activation of a dihydrogen molecule by a nickel(0)-borane complex, the empty p orbital of the borane moiety interacts with the H-H sigma bonding MO to form charge transfer (CT) from the dihydrogen molecule to the borane moiety to accelerate the reaction. In the B-F sigma-bond activation of BF3 by a platinum(0)-bisphosphine complex, the second BF3 molecule interacts with the F atom that is dissociating from the B atom to stabilize the transition state and product by the CT from the F atom to the second BF3. In this reaction, the substrate BF3 plays a crucial role as the Lewis acid to accelerate the activation of the B-F sigma bond. In the nickel-catalyzed decyanative coupling of arylcarboxybenzonitriles with acetylenes, two molecules of the aluminum Lewis acid interact with the cyano N atom and the carbonyl O atom of the substrate to stabilize the transition state and intermediate. In the nickel-catalyzed alkylation of aromatic amides with alkenes, the Lewis acid enhances the para regioselectivity of alkylation by interacting with the carbonyl O atom. In the nickel-catalyzed carboxylation of sp(3) carbon and sp carbon atoms with carbon dioxide, not the sigma-bond activation but the insertion reaction of carbon dioxide into the metal-carbon bond is accelerated by the Lewis acid by interacting with the O atom of carbon dioxide, because the CT from the metal-carbon bond to carbon dioxide is enhanced by the interaction. This theoretical knowledge suggests that the combination of transition-metal complex and Lewis acid can broaden the application range of transition-metal complex as catalyst.