Iron-catalyzed regioselective hydroaryloxylation of C≡C 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).