Magnesium-Ligand Cooperation Enables Regioselective Transfer Hydrogenation of Quinolines to 1,2-Dihydroquinolines
Biplab Mahata1,2, Jyoti Sharma2,3, Kumar Vanka2,3
1Inorganic Chemistry and Catalysis Division, Council of Scientific and Industrial Research (CSIR)-National Chemical Laboratory, Dr. Homi Bhabha Road, Pashan, Pune 411008, India.
Abstract:
We report the first magnesium-catalyzed regioselective reduction of quinolines to 1,2-dihydroquinolines, utilizing H3N·BH3. This protocol operates under mild conditions and tolerates a broad range of functional groups. Comprehensive mechanistic investigations, including kinetic analysis, deuterium labeling, and density functional theory calculations, elucidate a concerted hydride transfer pathway. This work serves as a blueprint for employing s-block metals with high-precision reactivity, which are traditionally reserved for transition metals.
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