Gold(III)‐Catalyzed Cyclization/Skeletal Rearrangement Reaction for the Synthesis of 2,4,6‐Trisubstituted 3‐Hydroxypyridines

Abstract 3‐Hydroxypyridines are attractive owing to their potential applications in medicinal chemistry. However, only a few reports on the synthesis of 2,4,6‐trisubstituted 3‐hydroxypyridines have been published to date. Herein, we describe a novel method for synthesizing 2,4,6‐trisubstituted 3‐hydroxypyridines. Au(III)‐catalyzed reactions using C ‐alkynyl‐ O ‐vinyl oximes via intramolecular nucleophilic addition, followed by skeletal rearrangement, including N−O bond cleavage. This protocol provides unprecedented 25 examples of 2,4,6‐trisubstituted 3‐hydroxypyridines with good functional and bulky‐group tolerances. Mechanistic studies suggest that the reaction proceeds through the generation of isoxazolium and nitrene species.