Transition Metal‐Free Diastereoselective Synthesis of β‐Carboline Tethered Dihydrofurocoumarin Derivatives

One‐pot procedure has been developed for the synthesis of novel β ‐carboline tethered trans 2,3‐furocoumarins via assembling 1‐formyl‐ β ‐carbolines, 4‐hydroxycoumarins, and phenacyl bromides in pyridine under transition metal‐free conditions. The strategy was also found applicable to gram scale synthesis and a library of 40 molecules has been developed. The significant features of this operationally facile approach includes high efficiency, short reaction time, excellent yields, multicomponent character of the reaction, metal‐free mild reaction conditions, and a column chromatography free purification procedure.