Recently, the paper "Selective Coupling of 1,2-Bis-Boronic Esters at the more substituted site through Visible-Light Activation of Electron Donor-Acceptor Complexes" co-authored by our group and Prof. Varinder Aggarwal's group at the University of Bristol, UK, was published in Angewandte Chemie. International Ed. in English (Angew. Chem. Int. Ed., 2022, DOI: 10.1002/anie.202202061).

Different from the popular transition metal-catalyzed and visible-light-catalyzed radical couplings, we used boronate complex with an electron-rich aryllithium which, in the presence of an electron-deficient aryl nitrile, leads to the formation of an Electron Donor–Acceptor complex (EDA complex). Following visible-light photoexcitation initiates SET to generate a radical ion pair comprised of boronate complex radical cation and (hetero)aryl radical anion. Homolytic cleavage of the primary C−B bond of boronate complex radical cation forms arylboronic ester and primary β-boryl radical, which undergoes rapid 1,2-boron shift to form the more stable secondary radical. The product was obtained after coupling of the persistent radical anion and secondary radical and elimination of cyanide. In this way, we can realize the arylation coupling reaction of boronate ester without using any transition metal catalyst and photocatalysis.

The postdoctoral fellow in Professor Aggarwal's research group, Hui Wang, is the first author of this paper. Besides, the first-grade PhD students Changlei Zhu and Zhaodong Zhu in our research group participated the mechanism verification experiments of the paper.