Abstract
The 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 Introduction
2 Inducing Regioselectivity via Ligand Control
3 A Comparison of o-Borylaryl Triflate Aryne Precursors to Kobayashi Aryne Precursors
4 Conclusion
Key words
catalysts - ligands - precursors - selectivity - aryne