Brønsted Acid-Mediated Multicomponent One-Pot Approach to Direct Construction of 4-Aryl-hydrocoumarin Derivatives.

The facile and efficient synthesis of a unique class of 4-aryl-hydrocoumarins having enormous applications in medicinal chemistry and natural products is presented. We have for the first time developed a Brønsted acid-catalyzed, multicomponent, one-pot approach for producing various 4-aryl-coumarin derivatives. The feedstock availability of these precursors allowed access to a wide range of 2-chromanone derivatives in good to excellent yields under mild conditions. The practicality of this protocol was justified by the synthesis of bioactive compounds, late-stage functionalization of natural products, and gram-scale synthesis.