Palladium-Catalyzed Intramolecular Alder-Ene Type Cycloisomerization Reactions

An overview of the recent literature on palladium-catalyzed intramolecular Alder-ene (IMAE) reaction of a variety of 1,n-unsaturated systems is presented. The reaction which was first reported by Trost and Lautens provided an efficient alternative to the thermal or Lewis acid catalyzed cycloisomerizations involving ene-type reaction. The IMAE cyclization of enynes and dienes has emerged as an important area and found significant applications in building up of complex molecular architectures and in the synthesis of several bioactive natural products. Since highly impactful reviews on this subject have covered the literature till 2015, this article focuses on summarizing the works subsequent to 2015.