Cover Feature: Quadruple Role of Pd Catalyst in Domino Reaction Involving Aryl to Alkyl 1,5‐Pd Migration to Access 1,9‐Bridged Triptycenes (Chem. Eur. J. 45/2021)

A Pd-catalyzed domino reaction of 1,8,13-tribromo-9-methoxytriptycenes is reported. Under conventional Suzuki coupling conditions, the triptycenes underwent multiple transformations to give 1,9-bridged triptycenes. Based on mechanistic investigations, a single Pd catalyst functions as Pd0, PdII and PdIV species catalyze four distinct processes: 1) aryl-to-alkyl 1,5-Pd migration, 2) intramolecular arylation, 3) homocoupling phenylboronic acid 4) coupling. More information can be found in Communication by T. Iwata, M. Shindo et al. (DOI: 10.1002/chem.202101728).