from first principles PP-I-1

PP-I-6activation barriers for the reactions of complex (12) with DIBAH (E = 6,6 kcal/mole) andDIBAC (E = 26,7 kcal/mole), one can conclude that the reaction between Cp 2 ZrHCl andHAlBu i 2 is more probable providing formation of monomer (15). As seen from the activationparameters for the reactions above initially there occurs the transformation (12) → (15) → (7).However, complex (7) has a lower activity since the activation barrier for its reaction witholefins is much higher (E = 26 kcal/mole) relative to (12) (E = 6,6 kcal/mol) and (15) (E = 7kcal/mol).Thus, a detailed research of mechanism of the olefin hydroalumination reaction allowedexplaining a reaction course on the basis of the energy barriers. The quantitative assessmentof the induction period found during laboratory experiments and its dependence upon initialamount of a catalyst and the type of olefin have been made.References:[1] Parfenova L.V., Pechatkina S.V., Khalilov L.M., Dzhemilev U.M. Investigation of the mechanismof olefins hydroalumination by alkilalans over Cp 2 ZrCl 2 // Herald of RAS, Chemical series, 2005. –V. 2 (in Russian).[2] Pankratyev E. Yu., etc. U. M. DFT Study on Mechanism of Olefin Hydroalumination by XAlBu i 2in the Presence of Cp 2 ZrCl 2 Catalyst. I. Simulation of Intermediate Formation in Reaction of HAlBu i 2with Cp 2 ZrCl 2 . // Organometallics. – 2009. – V. 28. – № 4. – P. 968-977.[3] Koledina K.F., etc. Determination of kinetic parameters of the private reactions of olefinshydroalumination ClAlBu i 2 / / Vestnik Bashkir University. - 2008. - T. 13. - № 3 (I). - C. 849-852 (inRussian).122