High‐Order Cascade Transformations on Tertiary β‐Enaminones for Step‐Economical Construction of Molecular Diversity and Complexity

The generation of molecular diversity and complexity constitutes the major task of synthetic organic chemistry. In contrast, to achieve the maximum complexity and/or diversity of organic compound with minimum operational steps is of high significance by saving consumption of both the chemicals and the time for synthesis, enhancing the synthetic efficiency and sustainability. Based on our longstanding interest in the enaminone‐based organic synthesis, herein, the research advances in high‐order cascade reactions are reviewed, which involve in the formation of at least four new chemical bonds, including sigma ‐, pi ‐bonds and CH bond, in one reaction of enaminones, showing how the high‐step economy is achieved in the enaminone‐based synthetic reactions. Since the known results all involves in the cyclization, the contents of the current manuscript are divided into two main sections: the single cyclization reaction and bicyclic annulation reaction.