Cu/TEMPO-Catalyzed Direct C2-Quaternization of Pyridines with Aldehydes via Sequential N–N Bond Formation and Cleavage
Pyridine represents an indispensable class of nitrogen-containing heteroarene, yet regioselective construction of an all-carbon quaternary center at the C2 position has remained a longstanding synthetic challenge. Here, we report a Cu/TEMPO-catalyzed regioselective C2 quaternization of pyridines with readily availabl...