Addition polymerization of three norbornene-type monomers derived from various diamines and cis-5-norbornene-exo-2,3-dicarboxylic acid anhydride in the presence of Pd complexes with an N-heterocyclic carbene ligand was studied. The polymerization conditions for these bifunctional polymers containing imide fragments were optimized, which made it possible to produce the target polymers in yields of up to 75

Addition polymerization of 3-methyl-3-phenylcyclopropene and 3,3-di(n-propyl)cyclopropene in the presence of a palladium complex containing an acyclic diaminocarbene ligand was studied. When activated with the organoborate (Na+[B(3,5-(CF3)2C6H3)4]–), such complex catalyzes the addition polymerization of substituted cyclopropenes. The polymerization occurs selectively without opening of the cyclopropane ring. The copolymerization of 3,3-di(n-propyl)cyclopropene with a monomer of the norbornene series (5-ethylidene-2-norbornene) was monitored by a decrease in the intensity of the characteristic signals in the 1H NMR spectra of the corresponding monomers. The substituted cyclopropenes were found to be more active monomers than norbornenes in the addition polymerization. The addition homopolymers of 3-methyl-3-phenylcyclopropene and 3,3-di(n-propyl)cyclopropene were characterized by differential scanning calorimetry, thermogravimetric analysis, and X-ray diffraction.

Addition polymerization of a norbornene derivative in the presence of palladium complexes containing acyclic diaminocarbene ligands was studied. Using the polymerization of 5-methyl-2-norbornene as an example, it was shown that such complexes at activation with an organoborate (Na + [B(3,5-(CF 3 ) 2 C 6 H 5 ) 4 ] – ) catalyze addition polymerization, thereby enabling synthesis of high-molecular-weight products with a unimodal molecular weight distribution. Analysis of the structure of the resulting polymer by 1 H NMR spectroscopy made it possible to establish that the polymerization proceeds selectively, without destruction of the bicyclic norbornane fragment. The synthesized addition poly(5-methyl-2-norbornene) was characterized by differential scanning calorimetry, thermogravimetric analysis, and WAXD analysis.

The polymerization of commercial strained cycloalkene, 5-ethylidene-2-norbornene, in the presence of Pd– N -heterocyclic carbene complexes (two of which are synthesized for the first time) containing phosphine or pyridine ligands is studied. Upon activation with borate Na + [B(3,5-(CF 3 ) 2 C 6 H 3 ) 4 )] – , the studied Pd complexes catalyze the polymerization of 5-ethylidene-2-norbornene according to the addition scheme. Polymerization proceeds selectively and involves only the endocyclic (norbornene) double bond of the monomer, while the exocyclic (ethylidene) double bond remains unaffected. Pd– N -heterocyclic carbene complexes with phosphine ligands are inactive in polymerization, while similar complexes with 3-chloropyridine ligands show a higher activity. Two new Pd complexes are synthesized.