ABSTRACT: A domino one‐pot synthesis of 2H‐chromenes and 4H‐chromenes starting from phenols and terminal acetylenes under solvent‐free and atom economy conditions, is described. This annulation reaction between phenols with alkynes, is promoted by simple Lewis acid ZnCl2. Significantly, to the best of our knowledge, the synthesis of 2H‐chromenes, is first of its kind, particularly, using terminal alkyl
An efficient and highlyselective approach for the synthesis of functionalized 4H-chromenes has been developed via gold(III)-catalyzed condensation/annulation tandem reaction of ketones with phenols.