Ab initio study for the hydrogen abstraction reactions on toluene and tetralin

The hydrogen abstraction reactions on toluene and tetralin are representative for reactions occurring in the thermolysis of phenethyl phenyl ether (PPE). PPE is used as a model compound to study the thermal decomposition of lignin, which is a naturally occurring biopolymer and a source of aromatic compounds and liquid fuels. The pyrolysis of PPE proceeds via a free radical chain mechanism where the product ratio is determined by the α/β-selectivity. To determine the factors which influence the selectivity, the relative rate constants of the participating hydrogen abstraction reactions were calculated. The reactions served to calibrate the methods since reliable experimental values for the relative rate constants and for the reaction enthalpies are available. This is an abstract of a paper presented at the 231st ACS National Meeting (Atlanta, GA 3/26-30/2006).