Multicomponent Direct Assembly of N -Heterospirocycles Facilitated by Visible-Light-Driven Photocatalysis.

N -heterospirocycles are interesting structural units found in both natural products and medicinal compounds but have relatively few reliable methods for their synthesis. Here, we enlist the photocatalytic generation of N -centered radicals to construct β-spirocyclic pyrrolidines from N -allylsulfonamides and alkenes. A variety of β-spirocyclic pyrrolidines have been constructed, including drug derivatives, in moderate to very good yields. Further derivatization of the products has also been demonstrated as has a viable scale-up procedure, making use of flow chemistry techniques.