Indole-fused pyridines are an important motif in pharmaceuticals and functional molecules. A visible-light induced Ru(bpy)3Cl2·6H2O catalyzed radical cascade sulfonylation/cyclization strategy for the synthesis of indole-fused pyridine derivatives was developed. Diverse indole-fused pyridines bearing different functional groups were obtained in moderate to good yields. Compared with previous work, the easily accessible starting materials, molecular nitrogen as byproduct, and eco-friendly visible light as an energy source all make this transformation more sustainable and practical.
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