Low-Energy Light-Driven Excited-State Palladium Catalysis: Cross-Coupling of Pyridine N-Oxides with Unactivated Alkyl
Jisun Kim1,2, Minyoung Ju3, Chaerin Baek3
1Chemical and Biological Integrative Research Center, Korea Institute of Science and Technology (KIST), 02792 Seoul, Republic of Korea.
Abstract:
Excited-state Pd catalysis has emerged as a new platform for cross-coupling reactions. Nonetheless, such catalysis typically requires high-energy near-ultraviolet (NUV) or blue (380-450 nm) light. In contrast, the use of lower-energy light (>520 nm) in excited-state Pd catalysis remains largely unexplored. Herein, we report a low-energy light-driven excited-state Pd-catalyzed cross-coupling of pyridine N-oxides with unactivated alkyl bromides. Mechanistic studies reveal the formation of a Pd(0)-pyridine N-oxide complex that absorbs low-energy light.
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