The reactivity and activation parameters for the ROMP of eight norbornene esters in the presence of a N-chelating Hoveyda–Grubbs II type catalyst were determined. Kinetic studies prove that these parameters highly depend on the monomer structures.

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1 H NMR spectroscopy is used to study the kinetics of metathesis copolymerization of three isomeric 2,3-dicarbomethoxy-5-norbornenes using the original N-chelating ruthenium carbene complex. Based on the experimental data the copolymerization constants of isomeric 2,3-dicarbomethoxy-5-norbornenes are calculated. It is shown that the relative reactivity of endic acid dimethyl ester-(1R,2S,3R,4S)-dimethyl bicyclo[2.2.1]hept-5-ene-2,3-dicarboxylate is almost two times lower than the corresponding values for (1R,2R,3S,4S)-dimethyl bicyclo[2.2.1]hept-5-ene-2,3-dicarboxylate, which confirms earlier findings of steric hindrance in the orientation of the monomer due to the carbene catalyst.

In recent years, the olefins metathesis has established itself as a powerful tool for carboncarbon bonds forming and has found numerous applications in polymer chemistry. One of the important directions of metathesis is the polymerization with cycle opening. A study of new ruthenium catalysts, resistant to the many functional groups effects, has showed the possibility of synthesizing functionalized polymers with unique properties. In this chapter, reactivity and activation parameters of eight different norbornene dicarboxylic acid alkyl esters in the presence of a Hoveyda-Grubbs II catalyst for the ring opening metathesis polymerization were determined by 1 H NMR analysis in-situ. The molecules of esters differ in the aliphatic radical structure and the location of the substituent groups. Kinetic studies have shown that effective polymerization constants and activation parameters strongly depend on the monomer structure. It is shown that the elongation of the aliphatic radical does not significantly affect the reactivity, but significantly changes the activation parameters. The branching of the aliphatic radical significantly affects both the reactivity of the corresponding ester and the activation parameters of the polymerization. The position of the substituents in the norbornene ring of the ester also has a significant effect on the activation parameters of metathesis polymerization.

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