Palladium-catalyzed selective oxidative olefination and arylation of 2-pyridones†
Substrate-controlled selective oxidative olefination of N-protected 2-pyridones has been achieved under palladium catalysis. The 5-position selectivity was followed for N-protected simple pyridones. Introduction of substituents into the 4- or the 6-position switched the site selectivity to the 3-position. Diolefination can also be achieved with high efficiency. Oxidative arylation with polyfluorobenzenes followed a similar selectivity except that the system is more sterically and electronically demanding.