Iodide Anion Modulates Halide Equilibrium in Cobalt-Catalyzed Cross-Electrophile Coupling to C-(Hetero)aryl
Hu-Yi Li1, Zhi-Jie Niu1, Mei-Ze Xu1
1State Key Laboratory of Natural Product Chemistry, School of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou730000, P. R. China.
Abstract:
C-(Hetero)aryl glycosides are privileged in pharmaceutical chemistry, yet their stereoselective synthesis remains challenging. We report an iodide-anion-enabled cobalt-catalyzed reductive cross-electrophile coupling of glycosyl chlorides with (hetero)aryl bromides, affording C-(hetero)aryl glycosides with high efficiency and stereoselectivity. Mechanistic studies reveal that iodide modulates halide coordination at cobalt, preventing Co-Cl deactivation and enabling the formation of the active L9-CoI2(II) species. This work establishes iodide as a multifunctional promoter in cobalt-catalyzed C-glycosylation.
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