Nickel Catalyzed Aryl–Aryl Bridging C–N Bond Activation of 2‑Pyridylpyridones and 6‑Purinylpyridones

A Ni-catalyzed
C–N bond activation of 2-pyridylpyridone
and 1-(9-alkyl 9H-purin-6-yl)pyridin-2(1H)-one and coupling with arylboronic acid have been achieved. A unique
feature of this reaction is the strategic activation of the bridging
C–N bond and replacement of the pyridone unit with aryl groups
using nickel catalyzed Suzuki–Miyaura coupling. This provides
an exciting new tool to build C–C bonds in the place of pyridones.
A wide variety of substrates and boronic acids are amenable to this
transformation. More importantly, we have successfully synthesized
a variety of C(6)-arylated purines via deaminative cross-coupling
which are very useful in developing unnatural nucleobases, nucleotides,
and nucleosides.