Ring-Opening Metathesis Polymerization (ROMP) in Ionic Liquids: Scope and Limitations

The ring-opening metathesis polymerization (ROMP) of functional norbornenes, i.e., exo,endo-5-norbornene-2-carbonitrile (3), methyl (exo,endo-5-norbornene-2-carboxylate) (4), norborn-5-ene-2-yl acetate (5), 2-propyl exo,endo-5-norbornene-2-carboxylate (6), norborn-5-ene-2-carboxylic acid (7), exo,endo-5-norbornene-2-methanol (8), exo,endo-5-norbornene-2-ylmethyl bromide (9), exo,endo-5-norbornene-2-ylmethylamine (10), exo,endo-5-norbornene-2-triethoxysilane (11), dimethyl exo,endo-5-norbornene-2-yl phosphonate (12), exo,endo-5-norbornene-2-ylcarboxyethyl-3-ethylimidazolium bis(trifluoromethylsulfonyl)imide (13), exo,endo-5-norbornene-2-ylcarboxyethyl-3-ethylimidazolium tetrafluoroborate (14), 7-oxanorborn-5-ene-2,3-dicarboxylic anhydride (15), was performed in a variety of pure ionic liquids (ILs) in the absence of any cosolvent. Both imidazolium, i.e., [1-butyl-3-methylIM]+X- and [1-butyl-2,3-dimethylIM]+X- (IM+ = imidazolium, X- = PF6-, CF3SO3-, (CF3SO2)2N-, CF3COO-, NO3-, BF4-, Br-), and phosphonium-ba...