A DENSITY FUNCTIONAL STUDY ON POLYMERIZATION PROCESSES CATALYZED BY Pd(II) BASED COMPLEXES

Artur Michalak  and Tom Ziegler ,

Department of Chemistry, University of Calgary, Calgary, Alberta Canada T2N 1N4.

We present a theoretical study on the polymerization and copolymerization reactions of ethene, a-olefins, and acrylates catalyzed by palladium-diimine complexes, N^N-Pd(II). Both, the model system, with N^N = -NH-CH-CH-NH-, and an example of a real catalysts, with N^N = -NAr-CR-CR-NAr-, Ar = -C₆H₅, -C₆H₃(Me)₂, -C₆H₃(i-Pr)₂, and R = H, -CH₃, C₁₀H₆ have been investigated. The study has focused on understanding how modifications of the N^N ligand influence the structure of the growing chain. Special attention has been given to the regioselectivity of olefin insertion into the Pd-C bond of primary, secondary, and tertiary carbon atoms. Relative insertion rates and stabilities of intermediates have been determined and compared with the experimental data.