Su Xiaoshi, Li Guoao, He Linke, Chen Shengda, Yang Xiaoliang, Wang Guoqiang, Li Shuhua
Institute of Theoretical and Computational Chemistry, Key Laboratory of Mesoscopic Chemistry of Ministry of Education, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, 210023, P. R. China.
State Key Laboratory of Coordination Chemistry, Jiangsu Key Laboratory of Advanced Organic Materials, Chemistry and Biomedicine Innovation Center (ChemBIC), School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, 210023, China.
Nat Commun. 2024 Aug 30;15(1):7549. doi: 10.1038/s41467-024-51997-0.
Nickel-catalyzed C-H bond functionalization reactions provide an impressive alternative to those with noble metal catalysts due to their unique reactivity and low cost. However, the regioselective C(sp)-H borylation reaction of arenes accomplished by nickel catalyst remains limited. We herein disclose a silyl-directed ortho C(sp)-H borylation of substituted arenes with a Ni(cod)/PMe/KHMDS catalyst system. Using readily available starting materials, this protocol provides easy access to ortho-borylated benzylic hydrosilanes bearing flexible substitution patterns. These products can serve as versatile building blocks for the synthesis of sila or sila/borine heterocycles under mild conditions. Control experiments and DFT calculations suggest that a catalytic amount of base prompts the formation of Ni(II)-Bpin-ate complex, likely related to the C(sp)-H bond activation. This borylation reaction might follow an unusual Ni(II)/Ni(IV) catalytic cycle.
镍催化的C-H键官能团化反应由于其独特的反应活性和低成本，为使用贵金属催化剂的反应提供了令人印象深刻的替代方案。然而，通过镍催化剂实现的芳烃区域选择性C(sp)-H硼化反应仍然有限。我们在此公开了一种使用Ni(cod)/PMe/KHMDS催化剂体系对取代芳烃进行硅基导向的邻位C(sp)-H硼化反应。该方法使用容易获得的起始原料，能够方便地得到具有灵活取代模式的邻位硼化苄基氢硅烷。这些产物可作为通用的结构单元，在温和条件下用于合成硅杂环或硅/硼杂环。对照实验和密度泛函理论计算表明，催化量的碱促使形成Ni(II)-Bpin-酸酯配合物，这可能与C(sp)-H键活化有关。这种硼化反应可能遵循一个不寻常的Ni(II)/Ni(IV)催化循环。
