Stereocontrolled construction of octahydroquinolizines, octahydroindolizines, hexahydrobenzo[a]quinolizines, and an octahydroindolo[2,3-a]quinolizine by an intramolecular double Michael reaction: synthesis of (±)epilupinine
trifluoromethanesulphonate in the presence of triethylamine at –78 to 20 °C. A simple synthesis of an alkaloid, (±)-epilupinine, was accomplished. Hexahydrobenzo[a]-quinolizin-4-ones and an octahydroindolo[2,3-a]quinolizin-4-one were also constructed by the same method.