Lewis Acid Catalyzed Cyclizative Rearrangement Strategy for One-Step 3-SF5- Furoquinoline and Furopyridine Synthesis

Pentafluorosulfanyl (SF5)-substituted polyheterocyclic architectures hold significant promise across pharmaceutical and materials science applications. Nevertheless, the lack of a general, modular synthetic strategy to convert readily available SF5-building blocks into structurally diverse SF5-polyheterocycles remains a persistent and unsolved challenge in modern heterocyclic chemistry. To address this gap, we report a single-step, atom-economical synthesis of 3-(pentafluoro-λ6-sulfanyl)-2-arylfuro[3,2-b]quinolines and 3-(pentafluoro-λ6-sulfanyl)-2arylfuro[3,2-b]pyridines. This transformation is catalyzed by inexpensive ZrCl4 and promoted by NaI, proceeding via a cascade cyclizative rearrangement: (i) regioselective 1,3-dipolar addition of quinoline or pyridine N-oxides to SF5-alkynes, (ii) sequential 1,3-oxygen transfer, and (iii) rearomatization—affording the target 3-SF5-polyheterocycles in yields up to 99%. The methodology exhibits broad functional group tolerance and practical utility, enabling late-stage diversification of drug-like molecules, modular assembly of value-added heterocyclic scaffolds, and rational construction of D–π–A-type push–pull fluorophores with enhanced photophysical properties. Collectively, this work provides a scalable, operationally simple route to SF5polyheterocycles, thereby advancing their accessible chemical space for discovery in medicinal and materials chemistry.