Synthesis of Heterocycles Using Tandem Cyclization Processes.

Various applications of the cycloaddition/N-acyliminium ion tandem cyclization cascade are outlined in this electronic symposium on synthetic organic chemistry. The key step in the process involves the generation of a reactive N-acyliminium ion by fragmentation of an amino substituted [4+2]-cycloadduct. The successful synthesis of a number of alkaloids by this sequence of reactions reveals the usefulness and importance of this unique domino cascade.