Controllable Diastereodivergent Synthesis of Pyrrolo­[2,1‑a]­isoquinolines via Catalytic Intramolecular Acylsulfenylation of Activated Alkenes

A controllable stereoselective synthesis of tetrahydro­pyrrolo­[2,1-a]­isoquinoline derivatives bearing a sulfur moiety was demonstrated with high diastereoselectivity through a catalytic intramolecular acylsulfenylation of activated alkenes. This approach involved a catalytic thia-Michael addition triggered intramolecular aldol-type tandem sequence. Both cis- and trans-products can be readily prepared in moderate to high yields with excellent diastereoselectivities in a catalytically atom-economic fashion under the optimized mild reaction conditions.