Pd(II)-Catalyzed Oxidative Naphthylation of 2‑Pyridone through N–H/C–H Activation Using Diarylacetylene as an Uncommon Arylating Agent

A Pd(II)-catalyzed straightforward
oxidative naphthylation
of unmasked
2-pyridone derivatives is described using a twofold internal alkyne
as a coupling partner. The reaction proceeds through N–H/C–H
activation to provide polyarylated N-naphthyl 2-pyridones.
An unusual oxidative annulation at the arene C–H bond of the
diarylalkyne leads to the formation of polyarylated N-naphthyl 2-pyridones, where the 2-pyridone-attached phenyl ring
of the naphthyl ring is polyaryl-substituted. Mechanistic studies
and DFT calculations suggest a plausible mechanism based on N–H/C–H
activation. The N-naphthyl 2-pyridone derivatives
were studied to explore encouraging photophysical properties.