Ligand-Free Iron-Catalyzed Carbonylation of Aryl Iodides with Alkenyl Boronic Acids: Access to α,β-Unsaturated Ketones.

The application of earth-abundant and low-toxicity iron catalysts as replacements for palladium in carbonylative coupling reactions remains challenging and largely unexplored. Reported here is a highly efficient iron-catalyzed carbonylation of aryl iodides with alkenyl boronic acids under ligand-free conditions, enabling the synthesis of α,β-unsaturated ketones even at atmospheric CO pressure. The broad applicability, including its effectiveness with α-branched enones and biologically active molecules, along with high yields and selectivity, underlines the general applicability of this catalytic system.