An Efficient Synthesis of Coumarin‐ and Quinolone‐Annulated Thiazole Derivatives via Ligand‐Free Iron (III)‐Catalyzed Coupling Followed by Acid‐Promoted Condensation.

Abstract An efficient strategy for the synthesis of coumarin- and quinolone-annulated thiazole derivatives using sodium sulfide as a sulfur source has been achieved via ligand-free iron (III)-catalyzed coupling followed by acid-promoted condensation. This synthetic protocol is one-pot, less expensive, and affords the products in good yields.