Wei Yi, Xie Xiao-Yu, Liu Jiabin, Liu Xiaoxiao, Zhang Bo, Chen Xin-Yi, Li Shi-Jun, Lan Yu, Hong Kai
Shanghai Engineering Research Center of Molecular Therapeutics and New Drug Development, School of Chemistry and Molecular Engineering, East China Normal University, 3663 N Zhongshan Road, Shanghai, 200062, China.
Green Catalysis Center, and College of Chemistry, Zhengzhou University, Zhengzhou, Henan, 450001, China.
Angew Chem Int Ed Engl. 2024 Apr 24;63(18):e202401050. doi: 10.1002/anie.202401050. Epub 2024 Mar 25.
Geminal bis(boronates) are versatile synthetic building blocks in organic chemistry. The fact that they predominantly serve as nucleophiles in the previous reports, however, has restrained their synthetic potential. Herein we disclose the ambiphilic reactivity of α-halogenated geminal bis(boronates), of which the first catalytic utilization was accomplished by merging a formal Heck cross-coupling with a highly diastereoselective allylboration of aldehydes or imines, providing a new avenue for rapid assembly of polyfunctionalized boron-containing compounds. We demonstrated that this cascade reaction is highly efficient and compatible with various functional groups, and a wide range of heterocycles. In contrast to a classical Pd(0/II) scenario, mechanistic experiments and DFT calculations have provided strong evidence for a catalytic cycle involving Pd(I)/diboryl carbon radical intermediates.
偕二硼酸酯是有机化学中用途广泛的合成砌块。然而，在以往的报道中，它们主要作为亲核试剂，这限制了它们的合成潜力。在此，我们揭示了α-卤代偕二硼酸酯的双亲性反应活性，其首次催化应用是通过将形式上的Heck交叉偶联与醛或亚胺的高非对映选择性烯丙基硼化反应相结合来实现的，为快速组装多官能化含硼化合物提供了一条新途径。我们证明了这种串联反应具有高效性，并且与各种官能团以及多种杂环兼容。与经典的Pd(0/II)反应情况不同，机理实验和密度泛函理论(DFT)计算为涉及Pd(I)/二硼基碳自由基中间体的催化循环提供了有力证据。
