Photoredox-Enabled Synthesis of β-Substituted Pyrroles from Pyrrolidines.

The merger of photoredox-initiated enamine-imine tautomerization and nucleophilic addition processes to access β-substituted pyrroles from pyrrolidines has been achieved. The significant advantage of this method is suppressing the Friedel-Crafts reaction, which usually occurs between N-aryl pyrrolidines and the highly electrophilic ketoesters. The good functional group tolerance, high atom economy, and high regioselectivity as well as easy handling conditions make it an appealing alternative to synthesize β-substituted pyrroles.