Liquid-Phase Pyrolysis of 1,2-Diphenylethane

Article abstract of DOI:10.1021/j150605a025

This paper presents results of a kinetic study of the deconposition of 1,2-diphenylethane in the liquid phase between 350 and 425 deg C along with a through mechanistic analysis of this system using thermochemical kinetics analysis and computer modeling.Toluene, trans-1,2-diphenylethene, and 1,1-diphenylethane are important products throughout the range of decomposition studied, with 1,2,3,4-tetraphenybutane being a major product in the early stages of reaction and diphenylmethane becoming important after extensive decomposition.Some noteworthy aspects of this reaction are the following: (1) all major product in the early stages of reaction can be quantitatively accounted for by a free-radical reaction model employing reasonable kinetic parameters; (2) trans-1,2-diphenylethene is formed by both a direct and indirect route involving α-1,2-diphenylethyl radicals; (3) 1,1-diphenylethane appears to be formed by a thermodynamically uphill 'neophyl' rearrangement; (4) above 10percent reaction secondary reactions lead to formation of diphenylmethane and noticeable divergence of predicted and observed product concentrations.This work presents the first use of thermochemical kinetics principles for analysis of complex liquid phase pyrolytic reactions and represents a first step toward establishing a reliable and self-consistent set of rate parameters for interpretation of these reactions.