Quantitative Structure-Thermostability Relationship of Late Transition Metal Catalysts in Ethylene Oligo/Polymerization
نویسندگان
چکیده
Quantitative structure–thermostability relationship was carried out for four series of bis(imino)pyridine iron (cobalt) complexes and α-diimine nickel complexes systems in ethylene oligo/polymerization. Three structural parameters were correlated with thermal stability, including bond order of metal-nitrogen (B), minimum distance (D) between central metal and ortho-carbon atoms on the aryl moiety and dihedral angle (α) of a central five-membered ring. The variation degree of catalytic activities between optimum and room temperatures (AT) was calculated to describe the thermal stability of the complex. By multiple linear regression analysis (MLRA), the thermal stability presents good correlation with three structural parameters with the correlation coefficients (R2) over 0.95. Furthermore, the contributions of each parameter were evaluated. Through this work, it is expected to help the design of a late transition metal complex with thermal stability at the molecular level.
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