Conversion of Diverse Aromatic Amines to 3-Acyl-Substituted Pyridine/Pyrimidine-Fused Heterocyclic Derivatives via the Combination of Rongalite and Enaminones

We describe a modular strategy for synthesizing seven types of 3-acyl-substituted fused pyridine and pyrimidine derivatives via an iodine-mediated, multicomponent tandem 3 + 1 + 2 annulation. This reaction employs rongalite and enaminones as C1 and C2 synthons and exhibits broad compatibility with various aromatic amines. The method offers significant advantages, including metal-free catalysis, simple operation, readily available starting materials, and high efficiency. Herein, we emphasize the versatility and divergent synthetic utility of this strategy, positioning it as a strategic extension for the construction of pyridine- and pyrimidine-fused heterocyclic scaffolds.