Photocyclisation of enamides. Part 21. Synthesis of benzo[a]quinolizines related to the alkaloids emetine and flavopereirine
Abstract
Acylation of 3,4-dihydro-1-methylisoquinoline with substituted acryloyl chlorides followed by irradiation of the resulting enamides provides a useful synthetic route to the benzo[a]quinolizines (4), (8a–d), and (9a) and (9b), and has been applied to a new total synthesis of flavopereirine (14).