Metal‐ and Oxidant‐Free Direct sp3 CH Arylation of Pyrrolidine

Arylated aliphatic N‐heterocycles, and particularly arylated pyrrolidines, have a wide range of applications in medicine as well as in chemistry. Arylation of pyrrolidines mainly relies on metal‐mediated couplings, which produce unwanted toxic metal waste. In this Communication, we report an oxidant‐ and metal‐free method for direct sp3 CH arylation of pyrrolidine employing a highly atom economic three‐component reaction. The method, operating under very simple and mild conditions, is highly selective and very efficient in producing single regioisomer of the arylated product even on a multigram scale. As an alternative to the metal‐mediated reaction, this method has the potential to be used in production at an industrial scale. Moreover, a new approach for CH arylation based on a novel reactivity that differs from the reactivity in Mannich or Betti reactions of iminium ion is presented.