A New Efficient Method for the Total Synthesis of Linear Furocoumarins

A new efficient method for the synthesis of linear furocoumarins by a Nef reaction and intramolecular cyclocondensation in one pot results in the construction of a benzofuran ring. This method provides a new strategy to furnish the benzofuran framework easily, and also allows the convenient synthesis of furocoumarin derivatives with different substituents on the coumarin ring by a subsequent Pechmann reaction. This strategy has also been applied to the preparation of four additional benzofuran derivatives.