Post-polymerization C À H activation of poly(quinoxaline-2,3-diyl)-based helically chiral phosphine ligands (PQXphos) with palladium(II) acetate afforded chiral phosphapalladacycles quantitatively. In situ generated palladacycles exhibited enantioselectivities up to 94 % ee in the palladium-catalyzed asymmetric ring-opening arylation of 1,4epoxy-1,4-dihydronaphthalenes with arylboronic acids.of 1,4-epoxy-1,4-dihydronaphthalenes with arylboronic acids. The application of these new chiral palladacycle catalysts to other catalytic reactions is now underway.