Iron-Catalyzed Regioselective Hydroaryloxylation of CC Triple Bonds: An Efficient Synthesis of 2H-1-Benzopyran Derivatives

An efficient, regioselective, iron-catalyzed intramolecular hydroaryloxylation of 2-propargylphenols or naphthols is reported. The reactions proceed through an endo-dig cyclization to afford benzopyran or naphthopyran derivatives in good to high yields using iron(III) chloride as the catalyst with the assistance of aniline in dimethylformamide (DMF).