A simple catalytic system, consisting of palladium iodide in conjunction with potassium iodide, was found to be very active in a variety of regio- and stereoselective cyclizations. In some cases the use of carbon monoxide or carbon monoxide/carbon dioxide mixtures in multistep reactions allowed the incorporation of one or both these species into the final product.

Catalytic one-pot procedures were achieved under mild conditions, thus providing a simple and direct way to functionalized heterocyclic molecules not readily obtainable by conventional methods.