Rhodium(III)-Catalyzed C-H Activation/Heterocyclization as a Macrocyclization Strategy. Synthesis of Macrocyclic Pyridones.

Structurally diverse macrocyclic pyridones can be efficiently synthesized by a rhodium(III)-catalyzed C-H activation/heterocyclization of ω-alkynyl α-substituted acrylic hydroxamates. The use of a O-pivaloyl hydroxamate as directing group was crucial to achieve efficient catalyst turnover in a redox-neutral process.