Enantioselective Synthesis of Boron-Stereogenic Heterocycles Enabled by Asymmetric Nickel Catalysis
Bin Ma1,2, Xinyue Tang3, Xin Zhou1,2
1Key Laboratory of Medicinal Chemistry for Natural Resource, Ministry of Education; Yunnan Key Laboratory of Research and Development for Natural Products, School of Pharmacy, Yunnan University, Kunming 650500, China.
Abstract:
Despite the widespread utilization of organoboron compounds across various areas, the efficient construction of stable and enantioenriched boron-centered chiral molecules remains a persistent challenge. Here, we present a nickel-catalyzed system for the asymmetric synthesis of boron-stereogenic heterocycles by the denitrogenative annulation reaction of benzotriazones with alkynes under mild conditions. Newly modified chiral BiIM ligands were the key factor in achieving high reactivity and stereoselectivity (up to 96% yield, 98% ee). This reaction not only enables access to a diverse range of highly functionalized chiral boron-centered compounds but also delivers optically active terminal/internal alkyne and isoquinolone moieties with various potential utility prospects. In addition, we demonstrated postsynthetic functionalization of natural products and drug molecules, along with the photophysical properties and bioimaging capabilities of these tailored boron-stereogenic heterocycles, underscoring their promise as chiral fluorescent probes and versatile platforms in multidisciplinary research.
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