A Decade of Indium-Catalyzed Multicomponent Reactions (MCRs)

In the context of synthetic chemistry, Indium is one of the least explored elements of the notorious group 13 of the periodic table and has not attracted quite the same amount of attention as its fellow members, Aluminium and Boron, which have shown unprecedented synthetic applications for more than half a century. Nonetheless, Indium has emerged in recent years as a very valuable catalyst for multicomponent reactions. From the use of indium powder or easily accessible and cheap indium salts to more complex indium-based metal-organic frameworks or nanoparticles, a plethora of applications has been described throughout this last decade, showcasing not only the versatility of indium catalysis but also how much there is still to be explored. In the aftermath of the international year of the periodic table of the chemical elements in 2019, we navigated through the large inventory of multicomponent reactions (MCRs) to encounter the types of useful reactions leading to important target compounds (many of which are biologically active) catalyzed by this d-block post-transition metal.