Department of Material Chemistry, Graduate School of Engineering, Kyoto University, Nishikyo-ku, Kyoto, 615-8510, Japan.
Fukui Institute for Fundamental Chemistry, Kyoto University, Sakyo-ku, Kyoto, 606-8103, Japan.
Angew Chem Int Ed Engl. 2023 Jun 5;62(23):e202300704. doi: 10.1002/anie.202300704. Epub 2023 Apr 26.
Despite the widespread success in the functionalization of C(sp )-H bonds, the deliberate functionalization of C(sp )-H bonds in a highly site- and stereoselective manner remains a longstanding challenge. Herein, we report an iridium/aluminum cooperative catalytic system that enables the β-selective C-H borylation of saturated cyclic amines and lactams. Furthermore, we have accomplished an enantioselective variant using binaphthol-derived chiral aluminum catalysts to forge C-B bonds with high levels of stereocontrol. Computational studies suggest that the formation of a Lewis pair with the substrates is crucial to lower the energy of the transition state for the rate-determining reductive elimination step.
尽管在 C(sp )-H 键的功能化方面取得了广泛的成功,但以高选择性和立体选择性方式对 C(sp )-H 键进行故意功能化仍然是一个长期存在的挑战。在此,我们报告了一种铱/铝协同催化体系,该体系能够实现饱和环状胺和内酰胺的β选择性 C-H 硼化。此外,我们还使用联萘酚衍生的手性铝催化剂实现了对映选择性变体,以高立体控制构建 C-B 键。计算研究表明,与底物形成路易斯对对于降低决定速率的还原消除步骤的过渡态的能量至关重要。