A new and efficient strategy for the stereoselective synthesis of tetrahydropyridino- and deazepanopyrrolo[1,2-c]imidazolidines has been developed. Annulation of acylethynylpyrroles with six- and seven-membered cyclic imines (MeCN/THF, 20–25 °C, 24–72 h) leads to tetrahydropyrrolo[1′,2′:3,4]imidazo[1,2-a]pyridines and hexahydropyrrolo[1′,2′:3,4]imidazo[1,2-a]azepines with (E)-acylethenyl moiety in 28–96% yields.
Key words
acylethynylpyrroles - tetrahydropyridines - deazepanes - annulation - tetrahydropyrrolo[1′,2’:3,4]imidazo[1,2-
a]pyridines - hexahydropyrrolo[1′,2′:3,4]imidazo[1,2-
a]azepines
