Abstract
This work reports the first synthesis of Δ(1)-pyrrolines promoted by visible light under continuous flow, achieved through the formal (3 + 2)-cycloaddition of 2H-azirines to enones. A total of 22 examples of trisubstituted Δ(1)-pyrrolines were prepared in only 30 min of residence time, with 41-93% yield and diastereomeric ratios up to 7:3. Furthermore, continuous flow conditions were also effective when chalcones were used as starting materials, leading to the formation of 7 tetrasubstituted pyrroles with an overall yield ranging from 12 to 47%, via a photocatalyzed cycloaddition-oxidation sequence.