Auto-tandem catalysis: a single catalyst activating mechanistically distinct reactions in a single reactor.

Domino reactions have received great attention as efficient synthetic methodologies for the construction of structurally complex molecules from simple materials in a single operation. Catalysts in domino reactions have also been well studied. In these reactions, a catalyst activates the substrate(s) only once, and the structure of the product is delineated at that time. Recently, the new concept of "tandem catalysis" in domino reactions, in which catalyst(s) sequentially activate more than two mechanistically distinct reactions, has been proposed. Tandem catalysis is categorized into three subclasses: orthogonal-, auto-, and assisted-tandem catalyses. Auto-tandem catalysis is defined as a process in which one catalyst promotes more than two fundamentally different reactions in a single reactor. An overview of recent and significant achievements in auto-tandem catalysis is presented in this paper.