Consecutive carbon-carbon bond formation approach in tandem cyclization reactions

The conventional tandem cyclization reactions involve the formation of alternating carbon-carbon bonds, whereas the newly developed cyclization reactions involve the formation of consecutive carbon-carbon bonds, in which N-aziridinylimines have been utilized as geminal radical acceptor and donor equivalents in a single operation. This unprecedented tandem cyclization approach becomes feasible by the successful generation of 5- and 6-membered ring radicals by radical cyclizations of N-aziridinylimines. The same notion can be applied to the anionic cyclizations of N-aziridinylimines, thereby allowing anionic consecutive carbon-carbon bond formation. This approach has great synthetic potential, particularly for the construction of quaternary carbon centers, and it provides highly efficient routes for the synthesis of natural products.