Sythesis and Retro Diels-Alder Decomposition of 1,4-Methanopyrrolo-,1,4-Methanopyrido- and 1,4-Methanoazepino[2,1-b]-quinazolinones1

Abstract From norbornane- and norbornene-fused azetidinones 1a and 1b, 1, 4-methanopyrrolo-, 1,4-methanopyrido- and 1,4-methanoazepino[2,1-b]quinazo-linones 6a, b-9a, b were prepared by ring enlargement. Norbornene derivatives 6b-9b underwent retrodiene decomposition to give pyrrolo-, pyrido- and azepino-[1, 2-αpyrimidinones 10–13, respectively.