Hu Meng-Yang, He Qiao, Fan Song-Jie, Wang Zi-Chen, Liu Luo-Yan, Mu Yi-Jiang, Peng Qian, Zhu Shou-Fei
State Key Laboratory and Institute of Elemento-Organic Chemistry, Tianjin, 300071, China.
Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), College of Chemistry, Nankai University, Tianjin, 300071, China.
Nat Commun. 2018 Jan 15;9(1):221. doi: 10.1038/s41467-017-02472-6.
Transition-metal-catalyzed alkene hydrosilylation is one of the most important homogeneous catalytic reactions, and the development of methods that use base metals, especially iron, as catalysts for this transformation is a growing area of research. However, the limited number of ligand scaffolds applicable for base-metal-catalyzed alkene hydrosilylation has seriously hindered advances in this area. Herein, we report the use of 1,10-phenanthroline ligands in base-metal catalysts for alkene hydrosilylation. In particular, iron catalysts with 2,9-diaryl-1,10-phenanthroline ligands exhibit unexpected reactivity and selectivity for hydrosilylation of alkenes, including unique benzylic selectivity with internal alkenes, Markovnikov selectivity with terminal styrenes and 1,3-dienes, and excellent activity toward aliphatic terminal alkenes. According to the mechanistic studies, the unusual benzylic selectivity of this hydrosilylation initiates from π-π interaction between the phenyl of the alkene and the phenanthroline of the ligand. This ligand scaffold and its unique catalytic model will open possibilities for base-metal-catalyzed hydrosilylation reactions.
过渡金属催化的烯烃硅氢化反应是最重要的均相催化反应之一，开发使用贱金属（尤其是铁）作为该转化反应催化剂的方法是一个不断发展的研究领域。然而，适用于贱金属催化烯烃硅氢化反应的配体骨架数量有限，严重阻碍了该领域的进展。在此，我们报道了在贱金属催化剂中使用1,10 - 菲咯啉配体进行烯烃硅氢化反应。特别是，具有2,9 - 二芳基 - 1,10 - 菲咯啉配体的铁催化剂对烯烃的硅氢化反应表现出意想不到的反应活性和选择性，包括对内部烯烃具有独特的苄基选择性、对末端苯乙烯和1,3 - 二烯具有马氏选择性以及对脂肪族末端烯烃具有优异的活性。根据机理研究，这种硅氢化反应不寻常的苄基选择性源于烯烃的苯基与配体的菲咯啉之间的π - π相互作用。这种配体骨架及其独特的催化模式将为贱金属催化的硅氢化反应开辟可能性。
