Dual Ligand Enabled\nPd-Catalyzed <i>Ortho</i>-Alkylation of Iodoarenes

The synthesis of complex polysubstituted aromatic molecules\nfrom\nsimple precursors is a central goal in organic chemistry. In this\nstudy, we developed an approach for the <i>ortho</i>-alkylation\nof iodoarenes utilizing a dual ligand catalytic system. By combining\nPd/olefin ligand cooperative catalysis with bulky trialkylphosphine\nligand-promoted C(sp<sup>2</sup>)–I reductive elimination,\nwe have established an <i>ortho</i>-alkylative Catellani-type\nreaction with the aryl-iodine bond reconstruction as the final step,\nwhich opens new synthetic opportunities within the Catellani-type\nreactions. Through in-depth mechanistic investigations, we have isolated\nand characterized key organopalladium intermediates, revealing the\nsynergistic interaction of the dual ligands in merging the Catellani-type\nprocess with C(sp<sup>2</sup>)–I reductive elimination. The\npresent study showcases the unique advantages of Pd/olefin ligand\ncatalysis and emphasizes the effectiveness of the dual ligand system\nin expanding the chemical space of the Catellani chemistry.