(η3‐allyl)palladium(II) catalysts for the addition polymerization of norbornene derivatives with functional groups

Cycloaliphatic polyolefins with functional groups were prepared by the Pd(II)‐catalyzed addition polymerization of norbornene derivatives. Homo‐ and copolymers containing repeating units based on bicyclo[2.2.1] hept‐5‐en‐2‐ylmethyl decanoate (endo/exo‐ratio = 80/20), bicyclo[2.2.1]hept‐5‐ene‐2‐carboxylic acid methyl ester (exo/endo = 80/20), bicyclo[2.2.1]hept‐5‐ene‐2‐methanol (endo/exo = 80/20), and bicyclo[2.2.1]hept‐5‐ene‐2‐carboxylic acid (100% endo) were prepared in 49–99% yields with {(η3‐allyl)Pd(BF4)} and {(η3‐allyl)Pd(SbF6)} as catalysts. The catalyst containing the hexafluoroantimonate ion was slightly more active than the tetrafluoroborate based Pd‐complex.