Cobalt-Catalyzed Migratory E-Selective Asymmetric Aza-Nozaki-Hiyama-Kishi Coupling
Yi Wang1, Yougui Luo1, Lifu Wu1
1State Key Laboratory of Coordination Chemistry, Engineering Research Center of Photoresist Materials Ministry of Education, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, China.
Abstract:
Transition-metal-catalyzed migratory cross-coupling offers an attractive strategy for converting readily available precursors into complex molecular architectures. However, current methods are typically restricted to a single migratory mode (e.g., chain-walking, through-space shift, or E/Z isomerization). Integrating multiple mechanistically distinct migratory events within a selective cross-coupling manifold to unlock new chemical space and diverse isomeric products remains a formidable challenge. Herein, we report a cobalt-catalyzed, migratory E-selective asymmetric aza-NHK (Nozaki-Hiyama-Kishi) coupling of ortho-iodophenylethylenes with imines. The key to this process is a synergistic sequence that combines a through-space 1,4-Co/H shift with alkenylcobalt E/Z isomerization. Notably, mixtures of E/Z-alkenyl bromides are also viable substrates, undergoing an unprecedented alkenylcobalt E/Z isomerization prior to E-selective asymmetric coupling. This method provides efficient access to high-value α-chiral (E)-allylic amines with exceptional control over regio-, E/Z-, and enantioselectivity.
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