A Stereoselective Domino Reaction Leading to a Pyrrolizidine Skeleton

Significance

Xu, Liu and colleagues report a new transformation of 1,4-dien-3-ones (1), which involves a tandem double Michael reaction followed by an intramolecular cyclization and an acyl migration. This one-pot process gives highly substituted azabicycles 3-5 and creates up to four adjacent stereocenters with complete regio- and diastereoselectivity. Using the achiral base catalyst DBU and thermal conditions, the authors obtained the desired products with good yields and demonstrated a broad substrate scope.