Catalytic Conjugate Addition of Indoles to 4-Aryl-4-oxobut-2-enoates by FeCl3

The conjugate addition of indoles to 4-aryl-4-oxobut-2-enoates was achieved with FeCl 3 as a catalyst under mild conditions. The reaction was highly regioselective and afforded a variety of new 3-substituted indoles in good to excellent yields.