Kinetics of reaction of triethylaluminium with oct-1-ene in diphenyl ether and thermodynamic parameters for the stability of the triethylaluminium–diphenyl ether complex

Abstract

Parameters for the equilibrium: ½Et₆Al₂+ Ph₂O [graphic omitted] Et₃Al,OPh₂ have been estimated by the n.m.r. chemical shift method: ΔH₄°=–16·3 ± 1·3 KJ mol^–1 and ΔS₄⊖=–42·7 ± 1·7 J mol^–1 K^–1(molar scale). The complex does not participate in the reaction with oct-1-ene. The retarded reaction in the presence of Ph₂O proceeds from the reduced concentration of the reactive, monomeric Et₃Al. The rate coefficient for the rate-controlling step Et₃Al + C₈H₁₆ [graphic omitted] Et₂Al(Decyl) is the same in Ph₂O and hydrocarbon solutions. If Smith's values of K₃ for Et₆Al₂⇌ 2Et₃Al are used, A₂= 10^{4·7 ± 0·1}| mol^–1 s^–1, E₂= 63·5 ± 1·2 kJ mol^–1. An error in previous calculations of k₂ for hydrocarbon solutions is corrected.