Synthesis of Substituted Pyridine Derivatives via the Ruthenium-Catalyzed Cycloisomerization of 3-Azadienynes

摘要

Due to the prominence of azaheterocycles in natural products,Pharmaceuticals,and functional materials,efficient methods for the synthesis of these compounds are of great value.The majority of synthetic routes to pyridine and quinoline derivatives rely on condensation reactions of amines and carbonyl compounds.The convergent synthesis of N-vinyl and N-aryl amides readily provides valuable precursors for the preparation of azaheterocycles (Scheme 1).Herein we report a mild and efficient two-step procedure for the conversion of N-vinyl and N-aryl amides to the corresponding substituted pyridines.