Regioselectivity of the insertion of propene with achiral Pd(ii) catalysts to highly isotactic poly[1-oxo-2-methylpropane-1,3-diyl]. Is the syndiotactic structure accessible?

Achiral cationic palladium catalysts, modified with 1,2-bis(diarylphosphinomethyl)benzene ligands with different electronic properties, can efficiently produce poly(propene-alt-CO) with essentially complete regioregularity and high isotacticity, depending on the aryl substituent; the stereochemistry of the copolymers obtained is barely, if at all, influenced by the regiochemistry of the olefin insertion.