Borane-Catalyzed C3-Alkylation of Pyridines with Imines, Aldehydes, or Ketones as Electrophiles
作者:Zhong Liu、Jia-Hao He、Ming Zhang、Zhu-Jun Shi、Han Tang、Xin-Yue Zhou、Jun-Jie Tian、Xiao-Chen Wang
DOI:10.1021/jacs.2c00962
日期:2022.3.23
The existing methods, including electrophilic aromatic substitution and C–H activation, often require harsh reaction conditions and excess pyridine and generate multiple regioisomers. Herein, we report a method for borane-catalyzed tandem reactions that result in exclusively C3-selective alkylation of pyridines. These tandem reactions consist of pyridine hydroboration, nucleophilic addition of the resulting
实现 C3 选择性吡啶官能化是有机化学中长期存在的挑战。现有的方法,包括亲电芳香取代和 C-H 活化,通常需要苛刻的反应条件和过量的吡啶,并产生多种区域异构体。在此,我们报告了一种硼烷催化串联反应的方法,该方法仅导致吡啶的 C3 选择性烷基化。这些串联反应包括吡啶硼氢化、所得二氢吡啶与亚胺、醛或酮的亲核加成,以及随后的氧化芳构化。由于吡啶是限制性反应物且反应条件温和,因此该方法构成了具有吡啶部分的结构复杂药物后期功能化的实用工具。