One pot hydroamination/[4 + 3] cycloaddition: synthesis towards the cyclohepta[b]indole core of silicine and ervatamine

A new and facile tandem reaction of intramolecular hydroamination and novel [4 + 3] cycloaddition was developed for the synthesis of multitudinal indole-containing 5,7,6-tricyclic skeletons. This method was further extended to the quick synthesis of a series of useful motif of natural products, such as the core of ervatamine and silicine.