Selective C(sp3)-H Cleavage of Enamides for Synthesis of 2-Pyridones via Ligand-Enabled Ni-Al Bimetallic Catalysis

Previously reported direct C-H functionalization reactions of enamides mainly occurred at vinylic C(sp(2))-H bonds because of their relatively high reactivity, while less reactive beta'-C(sp(3))-H activation has been rarely explored. Herein we report a selective C(sp(3))-H cleavage of N-formyl enamides without backbone modification, providing a series of 2-pyridones in 58-99% yields. A bifunctional phosphine oxide (PO) ligand-bridging Ni-Al bimetallic catalyst played key role in the reaction.

Automated summary

A selective C(sp(3))-H cleavage of N-formyl enamides without modifying the backbone to synthesize 2-pyridones in good yields was reported in this study. The use of a bifunctional phosphine oxide ligand-bridging Ni-Al bimetallic catalyst played a key role in the reaction.