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ABSTRACT:On the basis of quantum-chemical calculations, it was shown that among six types of active centers (ACs) that can form during the polymerization of butadiene with lanthanide-based catalytic systems, five types (containing electron-accepting chlorine atoms in the coordination sphere of a lanthanide) exhibit a -allyl binding of the terminal unit of a growing polymer chain to a lanthanide atom and function as cis-regulating. The sixth type of ACs is characterized by a -alkyl structure and shows a trans-stereospecificity. This results was used to interpret the data on the microstructure of polybutadiene prepared using NdCl 3 ⅐ 3TBP-Al(iso-C 4 H 9 ) 3 , NdCl 3 ⅐ 3TBP-Mg(n-C 4 H 9 )(iso-C 8 H 17 ) catalytic systems and their combinations (TBP is tributyl phosphate).

2) 35 6t66The reactivity of adamanmne-containing diamines in the reactions with dianhydrides of 3,4,3',4"-tetraearboxydiphenyl oxide was studied as a function of the parameters of their electronic structures. It was found that the reactivity changes in parallel with the charges on the N atoms, the energy of homolytic cleavage of the N--H bond, and the basicity of diamines.

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