Polymerization of Norbornene and Methyl Acrylate by a Bimetallic Palladium(II) Allyl Complex

The sequential reaction of {(allyl)Pd(μ-Cl)}2 (2) with AgPF6 and PCy3 in CH2Cl2 generates a mixture (1-in situ) of [{(allyl)Pd(PCy3)}2(μ-Cl)][PF6] (1), 2, [(allyl)Pd(PCy3)2][PF6] (3), and (allyl)PdCl(PCy3) (4), which evolves to form pure 1 after 20 h at 23 °C. Complex 1 reacts with PCy3 to generate 3 and 4 and undergoes facile exchange of Pd units with 4. Both 1 and 1-in situ polymerize mixtures of norbornene (NB) and methyl acrylate (MA) to a mixture of poly(NB) and poly(MA) via competing NB insertion polymerization and MA radical polymerization.