Insights into the Regioselectivity of Metal-Catalyzed Aryne Reactions

Abstract

AbstractThe synthetic potential of unsymmetrically substituted aryne intermediates is significantly hindered by regioselectivity issues. Current methods for inducing regioselectivity all rely on substrate control and are focused on non-metallated arynes. Before our initial disclosure, there was no systematic study regarding the regioselectivity of metal-catalyzed aryne reactions. By exploiting ligand control, we have induced regioselectivity in a palladium-catalyzed aryne annulation to form phenanthridinones (up to 9:91 r.r.). Through this study we have investigated: ligand effects, influence of steric perturbation, and the impact of the aryne precursor.1 Introduction2 Inducing Regioselectivity via Ligand Control3 A Comparison of o-Borylaryl Triflate Aryne Precursors to Kobayashi Aryne Precursors4 Conclusion