Ag(I)-C–H Activation Enables Near-Room Temperature Direct α-Arylation of Benzo[b]thiophenes

Research output: Contribution to journalArticle

  • Authors:
  • Chiara Colletto
  • Adyasha Panigrahi
  • Jaime Fernandez-casado
  • Igor Larrosa


The first example of near room temperature α-arylation of benzo[b]thiophenes is reported. The discovery rests on the observation of a switch in α-/β- regioselectivity at different loadings of Pd2(dba)3.CHCl3 in the coupling between benzo[b]thiophene and 4-iodotoluene. We show that this unprecedented regioselectivity switch is driven by a Ag(I)-mediated C–H activation at the α-C–H position, which becomes the dominant mode of reactivity at low concentrations of Pd. Competition experiments, kinetic studies, KIE and D/H scrambling experiments have been carried out supporting this mechanism.

Bibliographical metadata

Original languageEnglish
JournalJournal of the American Chemical Society
Early online date9 Jul 2018
Publication statusPublished - 2018