A novel and efficient stereo-controlled synthesis of hexahydroquinolinones via the diene-transmissive hetero-Diels–Alder reaction of cross-conjugated azatrienes with ketenes and electrophilic dienophiles
factors and the electronic demand of the substituents. The second Diels–Alder reaction of the initial [4+2] cycloadducts with electron-deficient dienophiles (TCNE, N-phenylmaleimide) stereoselectively yielded hexahydroquinolinone derivatives. Similarly, a tandem intermolecular–intramolecular mode of the aza-DTHDA reactions produced tetracyclic nitrogen-containing heterocycles in a regio- and stereoselective