Synthesis and ring-opening metathesis polymerization of new oxanorbornene dicarboximides with fluorine pendant groups

The synthesis of exo-N-3,5-bis(trifluoromethyl)phenyl-7-oxanorbornene-5,6-dicarboximide (TFMPhONDI, 2a), exo-N-4-fluorophenyl-7-oxanorbornene-5,6-dicarboximide (FPhONDI, 2b), and exo-N-pentafluorophenyl-7-oxanorbornene-5,6-dicarboximide (PFPhONDI, 2c) monomers is described. Poly(norbornene dicarboximide)s were obtained via ROMP using bis(tricyclohexylphosphine)benzylidine ruthenium(IV) dichloride (I) and tricyclohexylphosphine [1,3-bis(2,4,6-trimethylphenyl)-4,5 -dihydroimidazolilydene][benzylidene] ruthenium dichloride (II). Poly-TFMPhONDI (3a) bearing a trifluoromethylaryl moiety showed a higher T-g and improved mechanical properties as compared to poly-FPhONDI (3b) and poly-PFPhONDI (3c). [GRAPHICS]