Stereocontrolled synthesis of indolo[2,3-a]quinolizines by intramolecular double Michael reaction: proof for stepwise mechanism
Abstract
Indolo[2,3-a]quinolizines 3 were stereoselectively synthesized by the intramolecular double Michael reaction of amide esters 2, the indole nitrogen of which was protected with a tosyl group, using ButMe2SiOSO2CF3 in the presence of Et3N.